Apparatus for transmitting data in interleave division multiple access (idma) system

ABSTRACT

Provided is an apparatus including an acquisition unit that acquires an information block generated from transmission data for a user and subjected to error correction coding, and an interleaving unit that interleaves a bit sequence of the information block using an interleaver unique to the user. The interleaving unit interleaves the bit sequence by interleaving each of two or more partial sequences obtained from the bit sequence.

CROSS REFERENCE TO RELATED APPLICATIONS

The present disclosure is a continuation of U.S. patent application Ser.No. 17/508,177, filed Oct. 22, 2021, which is a continuation of U.S.patent application Ser. No. 16/898,779, filed Jun. 11, 2020, now U.S.Pat. No. 11,171,669 which is a continuation of U.S. patent applicationSer. No. 16/250,097, filed Jan. 17, 2019, now U.S. Pat. No. 10,771,093,which is a continuation of U.S. patent application Ser. No. 15/519,862,filed Apr. 18, 2017, now U.S. Pat. No. 10,224,965, which is a U.S.National Phase of International Patent Application No.PCT/JP2015/070650, filed Jul. 21, 2015, which claims the benefit ofpriority from prior Japanese Priority Patent Application JP 2014-218184filed in the Japan Patent Office on Oct. 27, 2014, the entire content ofwhich is hereby incorporated by reference. Each of the above-referencedapplications is hereby incorporated herein by reference in its entirety.

TECHNICAL FIELD

The present invention relates to an apparatus.

BACKGROUND ART

The number of users in cellular systems has significantly increased.Accordingly, systems of 5th Generation have been increasingly demanded.Shifting from 4th Generation to 5th Generation demands somebreakthroughs (e.g., improvement of both spectral efficiency and energyefficiency, and advanced radio frequency domain processing).

From the viewpoint of an improvement in spectrum efficiency, a multipleaccess technology (MAT) is one of the important elements. As multipleaccess technologies, interleave division multiple access (IDMA), filterbank multicarrier (IDMA), filter bank multicarrier (FBM), andnon-orthogonal multiple access (NOMA), and the like can be considered.In particular, in IDMA systems, interleavers can distinguish differentusers from each other and efficiently remove interference between theusers. Accordingly, design of interleavers is one of the most importantelements in an IDMA system. Each user uses an interleaver unique to theuser. As an interleaver becomes longer, correlation with an interleaverof a different user becomes lower, data of the different user can bedetected more easily, and performance of a bit error rate (BER)/blockerror rate (BLER) becomes more preferable.

For example, Non-Patent Literatures 1 to 5 have proposed interleaversfor IDMA systems. Specifically, Non-Patent Literature 1 proposes apseudo-random interleaver (PRI), Non-Patent Literature 2 proposes apower interleaver (PI), Non-Patent Literature 3 proposes a helicalinterleaver (HI), Non-Patent Literature 4 proposes a deterministicinterleaver (DI), and Non-Patent Literature 5 proposes a linearcongruential interleaver (LCI).

CITATION LIST Non-Patent Literature

-   Non-Patent Literature 1:Ioachim Pupeza, Aleksandar Kavicic and Li    Ping, Efficient Generation of Interleavers for IDMA,    Communications, 2006. ICC′ 06. IEEE International Conference, vol.    4, June 2006, pp. 1508 to 1513-   Non-Patent Literature 2:H. Wu, L. Ping and A. Perotti, User-specific    chip-level interleaver design for IDMA systems, Electronics Letters,    Vol. 42, Issue 4, February 2006, pp. 233 to 234-   Non-Patent Literature 3:Dapeng Hao and Peter Adam Hoecher, Helical    Interleaver Set Design for Interleave-Division Multiplexing and    Related Techniques, Communications Letters, IEEE, vol. 12, Issue 11,    November 2008, pp. 843-845-   Non-Patent Literature 4:Shu-Ming TSENG, IDMA based on Deterministic    Interleavers, Int. J. Communications, Network and System Sciences,    March 2010, pp. 94 to 97-   Non-Patent Literature 5:Tao Peng, Xiao-xin Yi, Kun Xu, and Lin-feng    Hu, Linear Congruential Interleavers Design for IDMA System, IEEE    ICCT 2011, September 2011.

DISCLOSURE OF INVENTION Technical Problem

However, for example, when an existing interleaver such as aninterleaver proposed in each of Non-Patent Literatures 1 to 5 or arandom interleaver (RI) is used, a burden on a terminal apparatus and asystem increases or flexibility of data transmission is lowered.

For example, when an RI is used, it is necessary for a transmitter totransmit an interleaver to a receiver. Therefore, a large memory isnecessary in the transmitter and an additional radio resource isnecessary in order for the transmitter to transmit the interleaver tothe receiver. That is, a burden on the transmitter and the systemincreases. In particular, when the number of users increases, data(interleavers) to be transmitted increases. As a result, memory shortageand delay or the like can occur. Also, even when the PRI proposed inNon-Patent Literature 1, the PI proposed in Non-Patent Literature 2, orthe HI proposed in Non-Patent Literature 3 is used, it is necessary fora transmitter to transmit an initial interleaver generated at random toa receiver. Therefore, even when the PRI, the PI, or the HI is used,there is a concern of the same problems occurring.

For example, when the DI proposed in Non-Patent Literature 4 or the LCIproposed in Non-Patent Literature 5 is used, an interleaver can begenerated in each of a transmitter and a receiver and it is notnecessary for the transmitter to transmit the interleaver to thereceiver. However, a bit sequence necessarily has a length of a power oftwo. Therefore, flexibility of data transmission is lowered.

Accordingly, it is desirable to provide a structure that makes itpossible to transmit data more flexibly and with a lesser burden in anIDMA system.

Solution to Problem

According to the present disclosure, there is provided an apparatusincluding: an acquisition unit configured to acquire an informationblock generated from transmission data for a user and subjected to errorcorrection coding; and an interleaving unit configured to interleave abit sequence of the information block using an interleaver unique to theuser. The interleaving unit interleaves the bit sequence by interleavingeach of two or more partial sequences obtained from the bit sequence.

Further, according to the present disclosure, there is provided anapparatus including: an acquisition unit configured to acquire areceived bit sequence; and a de-interleaving unit configured to generatea bit sequence of an information block not subjected to error correctiondecoding by de-interleaving the received bit sequence using ade-interleaver corresponding to an interleaver unique to a user. Thede-interleaving unit de-interleaves the received bit sequence byde-interleaving each of two or more partial sequences obtained from thereceived bit sequence.

Further, according to the present disclosure, there is provided anapparatus including: an acquisition unit configured to acquire aninformation block generated from transmission data for a user andsubjected to error correction coding; and an interleaving unitconfigured to interleave a bit sequence using an interleaver unique tothe user or another interleaver obtained from the interleaver unique tothe user and longer than the bit sequence of the information block.

Further, according to the present disclosure, there is provided anapparatus including: an acquisition unit configured to acquire areceived bit sequence; and a de-interleaving unit configured to generatea bit sequence of an information block not subjected to error correctiondecoding by de-interleaving the received bit sequence using ade-interleaver corresponding to another interleaver obtained from aninterleaver longer than the received bit sequence and unique to a user.

Further, according to the present disclosure, there is provided anapparatus including: an acquisition unit configured to acquire aninformation block generated from transmission data for a user; and aninterleaving unit configured to interleave a bit sequence of theinformation block using an interleaver unique to the user. Theinformation block is a block after segmentation for error correctioncoding and the error correction coding and before integration after theerror correction coding.

Further, according to the disclosure, there is provided an apparatusincluding: an acquisition unit configured to acquire a received bitsequence; and a de-interleaving unit configured to generate a bitsequence of an information block by de-interleaving the received bitsequence using a de-interleaver corresponding to an interleaver uniqueto a user. The information block is a block after segmentation for errorcorrection decoding and before the error correction decoding.

Advantageous Effects of Invention

According to the present disclosure described above, it is possible totransmit data more flexibly and with a lesser burden in an IDMA system.Note that the effects described above are not necessarily limited, andalong with or instead of the effects, any effect that is desired to beintroduced in the present specification or other effects that can beexpected from the present specification may be exhibited.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is an explanatory diagram illustrating an example of a schematicconfiguration of a system according to an embodiment.

FIG. 2 is a block diagram illustrating an example of a configuration ofa first radio communication apparatus according to the embodiment.

FIG. 3 is an explanatory diagram illustrating an example of atransmission process of the first radio communication apparatus.

FIG. 4 is an explanatory diagram illustrating a simplified example ofinterleaving.

FIG. 5 is a block diagram illustrating an example of a configuration ofa second radio communication apparatus according to the embodiment.

FIG. 6 is an explanatory diagram illustrating an example of a receptionprocess of the second radio communication apparatus.

FIG. 7 is an explanatory diagram illustrating a simplified example ofde-interleaving.

FIG. 8 is an explanatory diagram illustrating partial sequences andexamples of interleavers corresponding to the partial sequencesaccording to a first embodiment.

FIG. 9 is an explanatory diagram illustrating an example of aconcatenated interleaver according to the first embodiment.

FIG. 10 is a flowchart illustrating a first example of a schematic flowof a process according to the first embodiment.

FIG. 11 is a flowchart illustrating a second example of the schematicflow of a process according to the first embodiment.

FIG. 12 is an explanatory diagram illustrating an example of a firsttechnique of interleaving according to a second embodiment.

FIG. 13 is a flowchart illustrating an example of a schematic flow of aprocess related to a first technique according to the second embodiment.

FIG. 14 is a flowchart illustrating an example of a schematic flow of arepetition interleaving process related to the first technique accordingto the second embodiment.

FIG. 15 is an explanatory diagram illustrating an example of a secondtechnique of the interleaving according to the second embodiment.

FIG. 16 is a flowchart illustrating an example of a schematic flow of aprocess related to the second technique according to the secondembodiment.

FIG. 17 is a flowchart illustrating an example of a schematic flow of arepetition interleaving process related to the second techniqueaccording to the second embodiment.

FIG. 18 is an explanatory diagram illustrating another example of theinterleaving according to the second embodiment.

FIG. 19 is an explanatory diagram illustrating an example of aninterleaver according to a third embodiment.

FIG. 20 is a flowchart illustrating an example of a schematic flow of aprocess according to the third embodiment.

FIG. 21 is a flowchart illustrating an example of a schematic flow of aninterleaver generation process according to the third embodiment.

FIG. 22 is an explanatory diagram illustrating an example ofinterleaving according to a fourth embodiment.

FIG. 23 is an explanatory diagram illustrating a first example of codeblock concatenation according to the fourth embodiment.

FIG. 24 is an explanatory diagram illustrating a second example of thecode block concatenation according to the fourth embodiment.

FIG. 25 is an explanatory diagram illustrating a bit collection exampleof a code block according to the fourth embodiment.

FIG. 26 is a flowchart illustrating an example of a schematic flow of aprocess according to the fourth embodiment.

FIG. 27 is a block diagram illustrating a first example of a schematicconfiguration of an eNB.

FIG. 28 is a block diagram illustrating a second example of a schematicconfiguration of an eNB.

FIG. 29 is a block diagram illustrating an example of a schematicconfiguration of a smartphone.

FIG. 30 is a block diagram illustrating an example of a schematicconfiguration of a car navigation device.

MODE(S) FOR CARRYING OUT THE INVENTION

Hereinafter, (a) preferred embodiment(s) of the present disclosure willbe described in detail with reference to the appended drawings. In thisspecification and the appended drawings, structural elements that havesubstantially the same function and structure are denoted with the samereference numerals, and repeated explanation of these structuralelements is omitted.

Further, in the present specification and the drawings, elements of thesame names are distinguished from each other by suffixing differentalphabetic letters to the same reference numerals in some cases. Forexample, a plurality of elements having the same names such as partialsequences 13A, 13B, and 13C are distinguished from each other, asnecessary. However, when it is not necessary to distinguish a pluralityof elements having the same names from each other, only the samereference numerals are given. For example, when it is not particularlynecessary to distinguish the partial sequences 13A, 13B, and 13C fromeach other, the partial sequences 13A, 13B, and 13C are simply referredto as the partial sequences 13.

Also, the description will be made in the following order.

-   -   1. Examples of interleavers which can be generated by        transmitter and receiver    -   2. Schematic configuration of system    -   3. Configuration of each apparatus    -   3.1. Configuration of first radio communication apparatus    -   3.2. Configuration of second radio communication apparatus    -   4. First Embodiment    -   4.1. Overview    -   4.2. Example of interleaving    -   4.3. Technical features    -   5. Second Embodiment    -   5.1. Overview    -   5.2. First technique of interleaving    -   5.3. Second technique of interleaving    -   5.4. Variations of interleaving    -   5.5. Technical features    -   6. Third Embodiment    -   6.1. Overview    -   6.2. Example of interleaving    -   6.3. Technical features    -   7. Fourth Embodiment    -   7.1. Overview    -   7.2. Example of interleaving    -   7.3. Technical features    -   8. Fifth Embodiment    -   8.1. Overview    -   8.2. Technical features    -   9. Application examples    -   10. Conclusion

1. Examples of Interleavers which can be Generated by Transmitter andReceiver

For example, as examples of interleavers which can be generated by atransmitter and a receiver, there are a DI and an LCI. In other words,the interleavers are interleavers which can be generated based on acalculation equation.

(1) DETERMINISTIC INTERLEAVER (DI)

The DI is expressed by the following equation.

I(m)=((2k+1)m(m+1)/2)mod N  [Math. 1]

Here, k is a user ID. The user ID may be a radio network temporaryidentifier (RNTI). Further, m is a bit index of a bit in an input bitsequence. N is the length of an interleaver. In other words, N is thelength of the input bit sequence (that is, a total number of bits). I(m)is a value of an interleaver in regard to a bit of which a bit index ism. That is, a bit of which a bit index is m in an input bit sequence isoutput as a bit of which a bit index is I(m) in an output bit sequence.

As described above, a DI can be generated based on a user ID(k) and thelength of an interleaver (the length of an input bit sequence).

In the DI, N which is the length of an interleaver (the length of aninput bit sequence) is obtained as a power of two. When N is not a powerof two, values of interleavers can be the same for two or more bits withdifferent bit indexes in an input bit sequence. That is, I(a) and I(b)can be the same for mutually different a and b. As a result, performanceof BER/BLER can deteriorate.

Also, in a DI, I(0)=0 is established for any k and any N. That is,irrespective of a user and the length of an input bit sequence, thefirst bit in the input bit sequence is output as the first bit in anoutput bit sequence.

(2) Linear Congruential Interleaver (LCI)

An LCI is expressed by the following equation.

I(m)=(aI(m−1)+b)mod N

I(0)∈{0,N−1}  [Math. 2]

N is the length of an interleaver. In other words, N is the length of aninput bit sequence (that is, a total number of bits). As a firstcondition, b and N are relatively prime (that is, the maximum commondivisor of b and N is 1). As a second condition, a-1 is an integermultiple of any prime number p. Here, p is a value obtained by dividingN. As a third condition, a-1 is an integer multiple of 4 when N is aninteger multiple of 4. I(m) is a value of an interleaver for a bit ofwhich a bit index is m. That is, a bit of which a bit index is m in aninput bit sequence is output as a bit of which a bit index is 1(m) in anoutput bit sequence. Also, in the above-described equations, a parameterunique to a user is unnecessary.

In an LCI, as in a DI, N which is the length of an interleaver (thelength of an input bit sequence) is obtained as a power of two.

2. Schematic Configuration of System

A schematic configuration of a system 1 according to an embodiment ofthe present disclosure will be described with reference to FIG. 1 . FIG.1 is an explanatory diagram illustrating an example of a schematicconfiguration of a system 1 according to an embodiment. Referring toFIG. 1 , the system 1 includes a first radio communication apparatus 100and a second radio communication apparatus 200. The system 1 is a systemto which IDMA is applied.

The first radio communication apparatus 100 performs radio communicationwith other radio communication apparatuses. The second radiocommunication apparatus 200 performs radio communication with otherradio communication apparatuses.

For example, the first radio communication apparatus 100 transmits asignal to the second radio communication apparatus 200. Then, the secondradio communication apparatus 200 receives the signal. For example, thesecond radio communication apparatus 200 transmits a signal to the firstradio communication apparatus 100. Then, the first radio communicationapparatus 100 receives the signal.

One of the first radio communication apparatus 100 and the second radiocommunication apparatus 200 may be a base station and the other of thefirst radio communication apparatus 100 and the second radiocommunication apparatus 200 may be a terminal apparatus which cancommunicate with a base station. The base station may be a base stationof a cellular system.

3. Configuration of Each Apparatus

Next, an example of a configuration of each apparatus according to theembodiment of the present disclosure will be described with reference toFIGS. 2 to 7 .

3.1. Configuration of First Radio Communication Apparatus

First, an example of a configuration of the first radio communicationapparatus 100 according to the embodiment of the present disclosure willbe described with reference to FIGS. 2 to 4 . FIG. 2 is a block diagramillustrating an example of a configuration of the first radiocommunication apparatus 100 according to the embodiment of the presentdisclosure. Referring to FIG. 2 , the first radio communicationapparatus 100 includes an antenna unit 110, a radio communication unit120, a storage unit 130, and a processing unit 140.

(1) Antenna Unit 110

The antenna unit 110 radiates a signal output by the radio communicationunit 120 as radio waves to a space. Further, the antenna unit 110converts radio waves of a space into a signal and outputs the signal tothe radio communication unit 120.

(2) Radio Communication Unit 120

The radio communication unit 120 transmits or receives a signal. Forexample, the radio communication unit 120 transmits a signal to anotherapparatus and receives a signal from another apparatus.

(3) Storage Unit 130

The storage unit 130 temporarily or permanently stores a program anddata for operating the first radio communication apparatus 100.

(4) Processing Unit 140

The processing unit 140 provides various functions of the first radiocommunication apparatus 100. The processing unit 140 includes atransmission processing unit 150 and a reception processing unit 160.Also, the processing unit 140 may further include other constituentelements other than these constituent elements. That is, the processingunit 140 can also perform operations other than operations of theseconstituent elements.

(5) Transmission Processing Unit 150

The transmission processing unit 150 performs a transmission process oftransmitting transmission data for a user. The transmission processingunit 150 includes an information acquisition unit 151 and aninterleaving unit 153.

(a) Transmission Data

The first radio communication apparatus 100 may be a base station andthe transmission data may be transmission data destined for the user.Alternatively, the first radio communication apparatus 100 may be aterminal apparatus of the user and the transmission data may betransmission data from the user.

(b) Example of Transmission Process

FIG. 3 is an explanatory diagram illustrating an example of atransmission process of the first radio communication apparatus 100. Thetransmission process is a process of a physical layer when IDMA isapplied to a long term evolution (LTE) system.

S301: Generation of Transport Block (TB)

In a physical layer defined in LTE, a transport block (TB) istransmitted through a transmission chain. According to a size of asource, the maximum number of TBs transmitted with a physical downlinkshared channel (PDSCH) is calculated in advance. In LTE, a maximum oftwo transport blocks can be transmitted simultaneously. When the numberof transport blocks is obtained, a bit sequence of the transport blocksis generated.

S303: Cyclic Redundancy Check (CRC)

In LTE, CRC is used to perform error checking (that is, determinewhether data has been correctly transmitted). The CRC is added to agenerated transport block.

S305: Code Block Segmentation

For example, an error correction code is used as channel coding.Specifically, for example, turbo coding is used. Since a bit sequencewhich has the longest length imported to a turbo encoder is limited to6144 bits, a bit sequence exceeding 6144 bits is segmented into severalcode blocks (CBs). After the bit sequence is segmented, a CRC is addedto each CB.

In the CB segmentation, there are two criterions. A first criterion isthat the CB is not greater than 6144 bits. A second criterion is thatthe number of CBs is as small as possible.

Also, according to execution of the turbo coding, BER/BLER is calculatedbased on the CBs.

S307: Channel Coding

Error correction coding is performed as channel coding. In LTE, thechannel coding differs according to a channel.

In a process on a downlink shared channel (DL-SCH) and an uplink sharedchannel (UL-SCH), the turbo coding is used as the channel coding. Aturbo code is also referred to as a parallel concatenated convolutioncode (PCCC). A turbo encoder mainly includes two encoders and oneinterleaver. An input bit sequence is input directly through a firstencoder. Further, the input bit sequence is input to a second encoderafter passing through the interleaver. The turbo encoder outputs asystematic bit sequence and two parity bit sequences respectivelyencoded by the first and second encoders. The interleaver disposedbefore the second encoder plays an important role in performance of theturbo coding. In LTE, quadratic permutation polynomials (QPP) aredefined for the turbo coding.

Also, for example, a tail biting convolution code is used in a processon a broadcast channel (BCH).

S309: Rate Matching

In rate matching, the lengths of three bit sequences to be output areadjusted and sets of bits to be transmitted are extracted.

The rate matching includes subblock interleaving, bit collection, andbit selection. In the subblock interleaving, a systematic bit sequenceand two parity bit sequences are each randomized. In the bit collection,the three sequences are concatenated. In the bit collection, consecutivebits are extracted from a buffer.

S311: Code Block Concatenation

As described above, for example, a bit sequence exceeding 6144 bits issegmented into several code blocks (CBs). When the bit sequence issegmented, the CBs after the coding and the rate matching areconcatenated.

An output of CB concatenation is referred to as a codeword. Also, whenthe CB segmentation and the CB concatenation are not performed, anoutput of the rate matching is a codeword.

S313: Interleaving

In particular, in the embodiment of the present disclosure, the codewordis interleaved by an interleaver unique to a user. The interleaver maybe unique to a cell, a codeword (or a transport block), and/or a linkdirection (that is, a downlink or an uplink).

Also, not the interleaver but a scrambler is used for, for example, asystem to which orthogonal frequency-division multiple access (OFDMA) ora code division multiple access (CDMA) is applied.

S315: Modulation

In LTE, binary phase shift keying (BPSK), quadrature phase-shift keying(QPSK), 16 quadrature amplitude modulation (16QAM), and 64 quadratureamplitude modulation (64QAM) are supported as modulation schemes.Further, in LTE, a modulation scheme is selected according to a channelquality indicator (COI).

S317: Layer Mapping

After the modulation, a symbol is mapped to another layer. In LTE, acodeword is mapped to a maximum of four layers.

S319: Precoding

To maximize a system throughput in a MIMO system, precoding is necessaryaccording to a transmission mode. The transmission mode is set in openloop spatial multiplexing (OSLM).

S321: Resource Element Mapping

After precoding, a data sequence is mapped to radio resources in eachchannel. In LTE, a resource element (RE) and a resource block (RB) aredefined as radio resources.

Each radio frame includes ten subframes which is 10 ms, each of which is1 ms. Each subframe includes two slots, each of which is 0.5 ms. Eachslot includes six or seven symbols. One RE is a radio resource of onesymbol and one subcarrier. One RB is a radio resource of one slot andtwelve subcarriers (that is, 72 or 84 REs).

S323: OFDM Signal Generation

After the resource element mapping, an OFDM signal is generated. Thegeneration of the OFDM signal includes insertion of inverse fast Fouriertransform (IFFT) and a cyclic prefix (CP).

Also, the generated OFDM signal is converted from a digital signal to ananalog signal to be transmitted.

(c) Example of Interleaving

FIG. 4 is an explanatory diagram illustrating a simplified example ofinterleaving. Referring to FIG. 4 , an interleaver (2031) which has alength of 4 bits is illustrated. For example, when a bit sequence ABCDis input to the interleaver, the bit sequence is interleaved and a bitsequence BDAC is output.

(d) Operations of Information Acquisition Unit 151 and Interleaving Unit153

The information acquisition unit 151 acquires an information blockgenerated from transmission data for a user and subjected to the errorcorrection coding and the interleaving unit 153 interleaves a bitsequence of the information block.

For example, the information acquisition unit 151 and the interleavingunit 153 perform the above-described interleaving (S313). That is, theinformation acquisition unit 151 acquires the codeword generated fromthe transport block (transmission data) and subjected to the turbocoding (the information block subjected to the error correction coding)and the interleaving unit 153 interleaves the bit sequence of thecodeword.

Also, the interleaver used by the interleaving unit 153 may be mountedas hardware (for example, programmable hardware) or may be mounted assoftware. An interleave pattern of the interleaver may be replaceable.

(6) Reception Processing Unit 160

The reception processing unit 160 performs a reception process ofreceiving the transmission data for a user.

For example, the reception processing unit 160 performs the same processas a reception processing unit 250 of the second radio communicationapparatus 200 to be described below.

3.2. Configuration of Second Radio Communication Apparatus

Next, an example of a configuration of the second radio communicationapparatus 200 according to the embodiment of the present disclosure willbe described with reference to FIGS. 5 to 7 . FIG. 5 is a block diagramillustrating an example of the configuration of the second radiocommunication apparatus 200 according to the embodiment of the presentdisclosure. Referring to FIG. 5 , the second radio communicationapparatus 200 includes an antenna unit 210, a radio communication unit220, a storage unit 230, and a processing unit 240.

(1) Antenna Unit 210

The antenna unit 210 radiates a signal output by the radio communicationunit 220 as radio waves to a space. Further, the antenna unit 210converts radio waves of a space into a signal and outputs the signal tothe radio communication unit 220.

(2) Radio Communication Unit 220

The radio communication unit 220 transmits or receives a signal. Forexample, the radio communication unit 220 transmits a signal to anotherapparatus and receives a signal from another apparatus.

(3) Storage Unit 230

The storage unit 230 temporarily or permanently stores a program anddata for operating the second radio communication apparatus 200.

(4) Processing Unit 240

The processing unit 240 provides various functions of the second radiocommunication apparatus 200. The processing unit 240 includes areception processing unit 250 and a transmission processing unit 260.Also, the processing unit 240 may further include other constituentelements other than these constituent elements. That is, the processingunit 240 can also perform operations other than operations of theseconstituent elements.

(5) Reception Processing Unit 250

The reception processing unit 250 performs a reception process ofreceiving transmission data for a user. The reception processing unit250 includes an information acquisition unit 251 and a de-interleavingunit 253.

(a) Transmission Data

The second radio communication apparatus 200 may be a terminal apparatusof a user and the transmission data may be transmission data destinedfor the user. Alternatively, the second radio communication apparatus200 may be a base station and the transmission data may be transmissiondata from the user.

(b) Example of Reception Process

FIG. 6 is an explanatory diagram illustrating an example of a receptionprocess of the second radio communication apparatus 200. The receptionprocess is a process of a physical layer when IDMA is applied to an LTEsystem.

S351 to S357

After a signal is received, OFDM signal demodulation (S351) and resourceelement demapping (S353) are performed. Furthermore, a cell-specificreference signal (CRS) is retrieved (S355) and channel estimation isperformed using the CRS (S357).

S359: Equalization

An equalizer corrects distortion of a signal. As the equalizer, there isa linear equalizer or a nonlinear equalizer.

More specifically, as the equalizer, for example, there are zero forcing(ZF) equalizer, a minimum mean square error (MMSE) equalizer, and a softsphere decoder (SSD) equalizer. Theoretically, the SSD equalizer hasmore preferable performance of BER/BLER than the other two mainequalizers. To obtain lower calculation complexity, a maximum likelihooddetection (MLD) is mounted. However, when the degree of modulation andthe number of users increase, complexity of MLD considerably increases.To remedy the increase in the complexity, SSD equalization is performedin a certain area instead of treating all points inside signalconstellation. As a result, the complexity of calculation decreases.

S360: Multi-User Detection (MUD)

In MUD, elementary signal estimator (ESE) (S363), de layer mapping(S365), de-interleaving (S367), de rate matching (S369), deconcatenation(S371), and channel decoding (S373) are performed. In thede-interleaving (S367), an opposite operation to interleaving on atransmission side is performed. The channel decoding is, for example,error correction decoding. Specifically, the channel decoding is, forexample, turbo decoding.

Furthermore, in MUD, a feedback architecture is designed. Specifically,after the channel decoding (S373), a sequence is processed similarly tothe transmission side (S375 to S381). For example, interleaving isperformed (S379). In the interleaving, the same interleaver as theinterleaver on the transmission side is used.

In MUD, detection can be performed in parallel for all the users inorder to detect signals from different users. That is, bit sequences ofthe users can be detected simultaneously.

Also, when the second radio communication apparatus 200 is not a basestation but a terminal apparatus (that is, a user), a process ofdetecting a single user may be performed rather than MUD.

S383 to S387

Code block desegmentation (S383) and CRC checking (S385) are performedon the decoded code block. Then, the transport block is output (S387).

(c) Example of De-Interleaving

FIG. 7 is an explanatory diagram illustrating a simplified example ofde-interleaving. Referring to FIG. 7 , a de-interleaver (1302) which hasa length of 4 bits is illustrated. For example, when a bit sequence BDACis input to the de-interleaver, the bit sequence is interleaved and abit sequence ABCD is output.

(d) Operations of Information Acquisition Unit 251 and De-InterleavingUnit 253

The information acquisition unit 251 acquires a received bit sequenceand the de-interleaving unit 253 de-interleaves the received bitsequence to generate the bit sequence of the information block notsubjected to the error correction decoding.

For example, the information acquisition unit 251 and thede-interleaving unit 253 perform the above-described de-interleaving(S367). That is, the information acquisition unit 251 acquires areceived bit sequence after the ESE and de layer mapping. Then, thede-interleaving unit 253 generates the bit sequence of the codewordbefore the turbo decoding (the bit sequence of the information block notsubjected to the error correction decoding) by de-interleaving thereceived data sequence.

Also, the de-interleaver used by the de-interleaving unit 253 may bemounted as hardware (for example, programmable hardware) or may bemounted as software. A de-interleave pattern of the de-interleaver maybe replaceable.

(6) Transmission Processing Unit 260

The transmission processing unit 260 performs a transmission process oftransmitting transmission data for a user.

For example, the transmission processing unit 260 performs the sameprocess as the transmission processing unit 150 of the first radiocommunication apparatus 100 described above.

4. First Embodiment

Next, a first embodiment of the present disclosure will be describedwith reference to FIGS. 8 to 11 .

4.1. Overview (1) Technical Problem

As interleavers for an IDMA system, RI, PRI, PI, HI, DI, LCI, and thelike have been proposed.

However, for example, when such an existing interleaver is used in anIDMA system, a burden on a terminal apparatus and a system increases orflexibility of data transmission is lowered.

For example, when RI is used, a transmitter necessarily transmits aninterleaver to a receiver. Therefore, a large memory is necessary in thetransmitter. Additional radio resources are necessary in order for thetransmitter to transmit an interleaver to the receiver. That is, aburden on the transmitter and the system increases. In particular, whenthe number of users increases, data (interleavers) to be transmittedincreases. As a result, memory shortage and delay or the like can occur.Also, even when the PI proposed in Non-Patent Literature 2 or the HIproposed in Non-Patent Literature 3 is used, it is necessary for atransmitter to transmit an initial interleaver generated at random tothe receiver. Therefore, even when the PRI, the PI, or the HI is used,there is a concern of the same problems occurring.

For example, when the DI or the LCI is used, an interleaver can begenerated in each of the transmitter and the receiver and it is notnecessary for the transmitter to transmit the interleaver to thereceiver. However, a bit sequence necessarily has a length of a power oftwo. Therefore, flexibility of data transmission is lowered.

Accordingly, it is desirable to provide a structure that makes itpossible to transmit data more flexibly and with a lesser burden in anIDMA system. More specifically, for example, in the IDMA system, it isdesirable to provide a structure that makes it possible to transmit abit sequence which has any length without transmitting and receivinginterleavers between a transmission side and a reception side.

(2) Technical Means

In the first embodiment, the information acquisition unit 151 acquiresan information block after error correction coding generated fromtransmission data for a user. The interleaving unit 153 interleaves abit sequence of the information block using an interleaver unique to theuser. In particular, the interleaving unit 153 interleaves the bitsequence by interleaving each of two or more partial sequences obtainedfrom the bit sequence.

Furthermore, in the first embodiment, each of the two or more partialsequences is included in the bit sequence and does not overlap the otherof the two or more partial sequences.

Thus, for example, it is possible to transmit data more flexibly andwith a lesser burden in an IDMA system. More specifically, for example,a bit sequence which has any length can be transmitted withouttransmitting and receiving an interleaver between the transmission sideand the reception side in the IDMA system.

4.2. Example of Interleaving

Next, an example of interleaving according to the first embodiment willbe described with reference to FIGS. 8 to 11 .

(1) Partial Sequence and Interleaver

Any positive integer N can be expressed as a sum of powers of two asfollows.

$\begin{matrix}{{N = {\sum\limits_{i = 0}^{k}{a_{i}2^{i}}}},} & \left\lbrack {{Math}.3} \right\rbrack\end{matrix}$ a_(i) ∈ {0, 1}

Accordingly, even when a length M of a bit sequence of an informationblock (for example, a codeword) is not a length of a power of two, thelength M can be expressed as a sum of lengths of powers of two. In otherwords, the bit sequence can be divided into two or more partialsequences that each have a length of a power of two.

Accordingly, it is possible to generate an interleaver which is uniqueto a user and has the same length as the length of each partialsequence. For example, the interleaver is a DI. Hereinafter, a specificexample will be described with reference to FIG. 8 .

FIG. 8 is an explanatory diagram illustrating partial sequences andexamples of interleavers corresponding to the partial sequencesaccording to the first embodiment. Referring to FIG. 8 , a bit sequence11 with 1632 bits is illustrated. Here, 1632 is expressed as1024+512+64+32. Accordingly, the bit sequence 11 can be divided into apartial sequence 13A with 32 (=2⁵) bits, a partial sequence 13B with 64(=2⁶) bits, a partial sequence 13C with 512 (=2⁹) bits, and a partialsequence 13D with 1024 (=2¹⁰) bits. Therefore, interleavers 21corresponding the partial sequences 13 (that is, interleavers which areunique to users and have the same lengths as the lengths of the partialsequences 13) can be generated. Specifically, interleavers 21A, 21B,21C, and 21D respectively corresponding to the partial sequences 13A,13B, 13C, and 13D can be generated. For example, the interleaver 21 is aDI.

Also, one concatenated interleaver that includes the interleavercorresponding to each of the two or more partial sequences (interleaversthat are unique to users and have the same lengths as the lengths of thepartial sequences) and has the same length as the length of the bitsequence may be generated. When the interleaver corresponding to eachpartial sequence is a DI, the one concatenated interleaver may bereferred to as a concatenated deterministic interleaver (CDI).Hereinafter, a specific example will be described with reference to FIG.9 .

FIG. 9 is an explanatory diagram illustrating an example of aconcatenated interleaver according to the first embodiment. Referring toFIG. 9 , the interleavers 21A, 21B, 21C, and 21D described withreference to FIG. 8 are illustrated. For example, a concatenatedinterleaver 23 which has the same length as the length of the bitsequence 11 described with reference to FIG. 8 is generated by changinginput bits and output bits of the interleavers 21B, 21C, and 21D throughshifting and concatenating the changed interleavers 21A, 21B, 21C, and21D. For example, the input bits and the output bits of the interleaver21B are shifted by the length (that is, 32 bits) of the interleaver 21A.For example, the input bits and the output bits of the interleaver 21Care shifted by a sum (that is, 96 bits) of the lengths of theinterleavers 21A and 21B. For example, the input bits and the outputbits of the interleaver 21D are shifted by a sum (that is, 608 bits) ofthe lengths of the interleavers 21A, 21B, and 21C. For example, each ofthe interleavers 21A, 21B, 21C, and 21D is a DI and the concatenatedinterleaver 23 is a Ca

(2) Interleaving

For example, the interleaving unit 153 interleaves each of the two ormore partial sequences using the corresponding interleaver.

(a) First Example

As a first example, the interleaving unit 153 acquires a partialsequence in regard to each of two or more bit sequences included in abit sequence and interleaves the partial sequence using an interleavercorresponding to the partial sequence. Then, the interleaving unit 153concatenates the interleaved two or more partial sequences.

(a-1) Specific Example

Referring back to FIG. 8 , the interleaving unit 153 acquires thepartial sequence 13A and interleaves the partial sequence 13A using theinterleaver 21A corresponding to the partial sequence 13A. Similarly,the interleaving unit 153 interleaves the partial sequences 13B, 13C,and 13D. Then, the interleaving unit 153 concatenates the interleavedpartial sequences 13A, 13B, 13C, and 13D.

(a-2) Flow of Process

FIG. 10 is a flowchart illustrating a first example of a schematic flowof a process according to the first embodiment.

The information acquisition unit 151 acquires the information block (forexample, a codeword) generated from the transmission data (for example,a transport block) for a user and subjected to the error correctioncoding (S401).

The interleaving unit 153 acquires the partial sequences included in thebit sequence of the information block (S403). The partial sequence has alength of a power of two.

The interleaving unit 153 interleaves the partial sequences using theinterleavers corresponding to the partial sequences (S405). Theinterleavers have the same lengths as the lengths of the partialsequences. The interleavers are interleavers (for example, DIs) uniqueto the users.

When the interleaving on all the partial sequences included in the bitsequence ends (YES in S407), the interleaving unit 153 concatenates theinterleaved partial sequences (S409). Then, the process ends.

When the interleaving on any one of the partial sequences included inthe bit sequence does not end (NO in S407), the process returns to stepS403.

Also, of course, the interleaving of two or more partial sequences maybe performed in parallel.

(b) Second Example

As a second example, the interleaving unit 153 interleaves the bitsequence using one concatenated interleaver including an interleavercorresponding to each of two or more bit sequences included in a bitsequence.

(b-1) Specific Example

Referring back to FIGS. 8 and 9 , the interleaving unit 153 mayinterleave the bit sequence 11 using one concatenated interleaver 23including the interleavers 21A, 21B, 21C, and 21D corresponding to thepartial sequences 13A, 13B, 13C, and 13D included in the bit sequence11.

Also, the concatenated interleaver includes interleavers correspondingto partial sequences. Therefore, the second example is also the same asthe first example in that the partial sequences are interleaved usingthe interleavers corresponding to the partial sequences.

(b-2) Flow of Process

FIG. 11 is a flowchart illustrating a second example of the schematicflow of a process according to the first embodiment.

The information acquisition unit 151 acquires the information block (forexample, a codeword) generated from the transmission data (for example,a transport block) for a user and subjected to the error correctioncoding (S411).

The interleaving unit 153 generates one concatenated interleaverincluding the interleaver corresponding to each of two or more partialsequences included in a bit sequence of the information block (S413).The interleavers corresponding to the two or more partial sequences areinterleavers (for example, DIs) that have the same lengths as thelengths of the partial sequences and are unique to the users.

The interleaving unit 153 interleaves the bit sequence of theinformation block using the one concatenated interleaver (S415). Then,the process ends.

(3) De-Interleaving

Also, the second radio communication apparatus 200 performsde-interleaving corresponding to the above-described interleaving in thefirst radio communication apparatus 100.

Referring back to FIG. 8 , for example, the de-interleaving unit 253de-interleaves the partial sequences obtained from the received bitsequence using de-interleavers corresponding to the interleavers 21A,21B, 21C, and 21D. As a result, the bit sequence 11 including thepartial sequences 13A, 13B, 13C, and 13D can be obtained.

Referring back to FIGS. 8 and 9 , the de-interleaving unit 253 mayde-interleave the received bit sequence using the de-interleaverscorresponding to the concatenated interleaver 23. As a result, the bitsequence 11 may be obtained. Also, the de-interleaver corresponding tothe concatenated interleaver 23 includes the de-interleaverscorresponding to the interleavers 21A, 21B, 21C, and 21D. Therefore,this example is also substantially the same as the above-describedexample.

4.3. Technical Features (1) Interleaving

As described above, in the first embodiment, the information acquisitionunit 151 acquires the information block generated from the transmissiondata for the user and subjected to the error correction coding. Theinterleaving unit 153 interleaves the bit sequence of the informationblock using the interleaver unique to the user. In particular, theinterleaving unit 153 interleaves the bit sequence by interleaving twoor more partial sequences obtained from the bit sequence.

Furthermore, in the first embodiment, each of the two or more partialsequences is included in the bit sequence and does not overlap the otherof the two or more partial sequences.

(a) Transmission Data

The first radio communication apparatus 100 may also be a base stationand the transmission data may also be transmission data destined for theuser. Alternatively, the first radio communication apparatus 100 mayalso be a terminal apparatus of the user and the transmission data maybe transmission data from the user.

For example, the transmission data is a transport block.

(b) Information Block

For example, the information block is a codeword. Alternatively, as in afourth embodiment to be described below, the information block may alsobe a code block.

(c) Bit Sequence of Information Block

For example, the bit sequence of the information block has a lengthwhich is not a power of two.

Referring back to FIG. 8 , for example, the bit sequence is the bitsequence 11 and has a length of 1632 bits.

(d) Partial Sequences

As described above, each of the two or more partial sequences isincluded in the bit sequence and does not overlap the other of the twoor more partial sequences.

For example, the two or more partial sequences each have a length of apower of two. Furthermore, for example, the two or more partialsequences have different lengths. Furthermore, for example, a total sumof the lengths of the two or more partial sequences is equal to thelength of the bit sequence.

Referring back to FIG. 8 , for example, the two or more partialsequences are the partial sequences 13A, 13B, 13C, and 13D. Each of thepartial sequences 13A, 13B, 13C, and 13D is included in the bit sequence11 and does not overlap the other partial sequences. Furthermore, thepartial sequences 13A, 13B, 13C, and 13D each have lengths of powers oftwo and have different lengths. Furthermore, a total sum of the lengthsof the partial sequences 13A, 13B, 13C, and 13D is equal to the lengthof the bit sequence 11.

(e) Interleaving

For example, the interleaving unit 153 interleaves each of the two ormore partial sequences using the corresponding interleaver.

(e-1) Interleaver

For example, the corresponding interleaver is an interleaver which hasthe same length as the length of the partial sequence and is unique tothe user. Furthermore, the corresponding interleaver may be aninterleaver unique to the transmission data (for example, a transportblock) or the information block (for example, a codeword or a codeblock).

For example, the corresponding interleaver is an interleaver which canbe generated in each of a transmitter and a receiver (in other words, aninterleaver which can be generated based on a calculation equation). Forexample, the corresponding interleaver is a DI. As another example, thecorresponding interleaver may be an LCI. Also, the correspondinginterleaver is not limited to these examples.

The corresponding interleaver may also be mounted as hardware (forexample, programmable hardware) or may also be mounted as software. Aninterleave pattern of the corresponding interleaver may be replaceable.

(e-2) Specific Example

Referring back to FIG. 8 , for example, the interleaving unit 153interleaves the partial sequence 13A using the interleaver 21A.Similarly, the interleaving unit 153 interleaves the partial sequence13B using the interleaver 21B, interleaves the partial sequence 13Cusing the interleaver 21C, and interleaves the partial sequence 13Dusing the interleaver 21D.

(e-3) Parallel Process

The interleaving unit 153 may interleave the two or more partialsequences in parallel. Thus, the interleaving can be performed morerapidly.

(e-4) Concatenated Interleaver

The interleaving unit 153 may interleave the bit sequence using oneconcatenated interleaver which includes an interleaver corresponding toeach of the two or more partial sequences and has the same length as thelength of the bit sequence.

Referring back to FIGS. 8 and 9 , the concatenated interleaver 23includes the interleavers 21A, 21B, 21C, and 21D and has the same lengthas the length of the bit sequence 11. The interleaving unit 153 mayinterleave the bit sequence 11 using the concatenated interleaver 23.Also, even in this case, each of the partial sequences 13A, 13B, 13C,and 13D is substantially interleaved using the corresponding interleaver21.

As described above, the interleaving unit 153 interleaves the bitsequence of the information block. Thus, for example, it is possible totransmit data more flexibly and with a lesser burden in the IDMA system.

More specifically, for example, in the IDMA system, it is possible totransmit a bit sequence which has any length without transmitting andreceiving interleavers between a transmission side and a reception side.For example, since the interleaver may not be transmitted and receivedbetween the transmitter and the receiver, a large memory is notnecessary in the transmitter and additional radio resources are notnecessary either. Therefore, it is possible to reduce a burden on thetransmitter and the system. Further, since the length of the bitsequence of the information block is not limited to a power of two, itis possible to transmit data more flexibly.

Also, in the first embodiment, since bits included in the bit sequenceare interleaved only once, it is possible to shorten an interleavingprocess.

(2) De-Interleaving

The information acquisition unit 251 acquires a received bit sequence.The de-interleaving unit 253 generates a bit sequence of the informationblock not subjected to error correction decoding by de-interleaving thereceived bit sequence using de-interleavers corresponding tointerleavers unique to users. In particular, the de-interleaving unit253 de-interleaves the received bit sequence by de-interleaving two ormore partial sequences obtained from the received bit sequence.

Furthermore, in the first embodiment, each of the two or more partialsequences is included in the received bit sequence and does not overlapthe other of the two or more partial sequences.

(a) Information Block

For example, the information block is a codeword. Alternatively, as inthe fourth embodiment to be described below, the information block mayalso be a code block.

(b) Received Bit Sequence

For example, the received bit sequence is a sequence received in asubframe. For example, the received bit sequence is a sequence after ESEand de layer mapping. For example, the received bit sequence has alength which is not a power of two.

(c) Partial Sequences

As described above, each of the two or more partial sequences isincluded in the received bit sequence and does not overlap the other ofthe two or more partial sequences.

For example, the two or more partial sequences each have a length of apower of two. Furthermore, for example, the two or more partialsequences have different lengths. Furthermore, for example, a total sumof the lengths of the two or more partial sequences is equal to thelength of the received bit sequence.

(d) De-Interleaving

For example, the de-interleaving unit 253 de-interleaves each of the twoor more partial sequences using the corresponding de-interleaver.

(d-1) De-Interleaver

For example, the corresponding de-interleaver is a de-interleaver whichhas the same length as the length of the partial sequence andcorresponds to the interleaver unique to the user.

For example, the interleaver unique to the user is an interleaver whichcan be generated in each of a transmitter and a receiver (in otherwords, an interleaver which can be generated based on a calculationequation). For example, the interleaver unique to the user is a DI. Asanother example, the interleaver unique to the user may be an LCI. Also,the interleaver unique to the user is not limited to the examples.

The corresponding interleaver may also be mounted as hardware (forexample, programmable hardware) or may also be mounted as software. Ade-interleave pattern of the corresponding de-interleaver may bereplaceable.

(d-2) Specific Example

Referring back to FIG. 8 , for example, the de-interleaving unit 253de-interleaves the partial sequences obtained from the received bitsequence using the de-interleavers corresponding to the interleavers21A, 21B, 21C, and 21D. As a result, the bit sequence 11 including thepartial sequences 13A, 13B, 13C, and 13D can be obtained.

(d-3) Parallel Process

The de-interleaving unit 253 may de-interleave the two or more partialsequences in parallel. Thus, the de-interleaving can be performing morerapidly.

(d-4) Concatenated De-Interleaver

The de-interleaving unit 253 may de-interleave the received bit sequenceusing one concatenated de-interleaver that includes de-interleaverscorresponding to the two or more partial sequences and has the samelength as the length of the received bit sequence.

Referring back to FIGS. 8 and 9 , for example, de-interleaving unit 253may de-interleave the received bit sequence using a de-interleavercorresponding to the concatenated interleaver 23. As a result, the bitsequence 11 may be obtainable. Also, the de-interleaver corresponding tothe concatenated interleaver 23 includes the de-interleaverscorresponding to the interleavers 21A, 21B, 21C, and 21D.

5. Second Embodiment

Next, a second embodiment of the present disclosure will be describedwith reference to FIGS. 12 to 18 .

5.1. Overview (1) Technical Problem

A technical problem according to the second embodiment is the same asthe technical problem according to the first embodiment. Accordingly,the repeated description thereof will be omitted here.

(2) Technical Means

In the second embodiment, the information acquisition unit 151 acquiresan information block generated from transmission data for a user andsubjected to error correction coding. The interleaving unit 153interleaves a bit sequence of the information block using an interleaverunique to the user. In particular, the interleaving unit 153 interleavesthe bit sequence by interleaving two or more partial sequences obtainedfrom the bit sequence.

Furthermore, in the second embodiment, at least one of the two or morepartial sequences includes a part of a sequence obtained by interleavingthe other of the two or more partial sequences. That is, at least a partof the bit sequence is interleaved repeatedly.

Thus, for example, it is possible to transmit data more flexibly andwith a lesser burden in an IDMA system. More specifically, for example,a bit sequence which has any length can be transmitted withouttransmitting and receiving an interleaver between the transmission sideand the reception side in the IDMA system.

5.2. First Technique of Interleaving

Next, a first technique of the interleaving according to the secondembodiment will be described with reference to FIGS. 12 to 14 .

(1) Length/Interleaver

In the first technique, a length according to the length M of a bitsequence of the information block (for example, a codeword) is selectedfrom a plurality of predetermined lengths and an interleaver with theselected length is used. In other words, the interleaver which has thelength according to the length M of the bit sequence is selected from aplurality of predetermined interleavers which have predetermineddifferent lengths.

Specifically, for example, a maximum length is selected from one or morelengths equal to or less than the length M included in the plurality ofpredetermined lengths. In other words, a longest interleaver is selectedfrom one or more interleavers which have lengths equal to or less thanthe length M and are included in the plurality of predeterminedinterleavers.

For example, the plurality of predetermined lengths are 128 bits, 256bits, 512 bits, 1024 bits, 2048 bits, and 4096 bits. The length M of thebit sequence is 1632 bits. In this case, of four lengths (128 bits, 256bits, 512 bits, and 1024 bits) equal to or less than 1632 bits, thelongest length which is 1024 bits is selected. As a result, aninterleaver which has the length of 1024 bits is used. That is, theinterleaver which has the length of 1024 bits is selected.

Also, the bit sequence is a bit sequence of an information blockgenerated from transmission data for a user and the interleaver is aninterleaver unique to the user. For example, the interleaver has alength of a power of two. For example, the interleaver is a DI.

(2) Interleaving

When the selected length is equal to the length M of the bit sequence,as described above, the interleaving unit 153 interleaves the bitsequence using an interleaver which has the selected length (that is,the selected interleaver).

Conversely, when the selected length is less than the length M of thebit sequence, as described above, the interleaving unit 153 interleavestwo or more partial sequences obtained from the bit sequence using theinterleaver which has the selected length (that is, the selectedinterleaver). In particular, the interleaving unit 153 interleaves apart of the bit sequence repeatedly. Hereinafter, a specific examplewill be described with reference to FIG. 12 .

FIG. 12 is an explanatory diagram illustrating an example of a firsttechnique of interleaving according to the second embodiment. Referringto FIG. 12 , a bit sequence 31 which has the length M is illustrated. Inthis case, a length K according to the length M is selected from aplurality of predetermined lengths. That is, an interleaver which hasthe length K according to the length M is selected from the plurality ofpredetermined interleavers. For example, the length M is 1632 bits andthe length K is 1024 bits. First, a partial sequence 33 (0-th to k−1-thbits) which has a length K in the bit sequence 31 is interleaved usingthe selected interleaver. As a result, a sequence 37 is obtained.Thereafter, the sequence 37 is concatenated with a remaining sequence 35(K-th to M−1-th bits) in the bit sequence 31. Furthermore, a partialsequence (M-K-th to M−1-th bits) which has the length K in theconcatenated bit sequence is interleaved using the selected interleaver.A partial sequence 43 includes a sequence 39 in the sequence 37 and aremaining sequence 35 in the bit sequence 31. Then, by concatenating aremaining sequence 41 (in other words, the remaining sequence 41 in theconcatenated bit sequence) in the sequence 37 and a sequence 45 obtainedby interleaving the partial sequence 43, it is possible to obtain aninterleaved bit sequence 47.

(3) Flow of Process (a) Overall Flow

FIG. 13 is a flowchart illustrating an example of a schematic flow of aprocess related to the first technique according to the secondembodiment.

The information acquisition unit 151 acquires the information block (forexample, a codeword) generated from the transmission data (for example,a transport block) for a user and subjected to the error correctioncoding (S431).

The interleaving unit 153 selects the length K according to the length Mof the bit sequence of the information block from the plurality ofpredetermined lengths (S433). The length K is the maximum length amongone or more lengths equal to or less than the length M and included inthe plurality of predetermined lengths.

When the selected length K is equal to the length M of the bit sequenceof the information block (YES in S435), the interleaving unit 153interleaves the bit sequence of the information block using theinterleaver which has the selected length K (that is, the selectedinterleaver). Then, the process ends.

When the selected length K is less than the length M of the bit sequenceof the information block (NO in S435), the interleaving unit 153performs a repetition interleaving process (S440). Then, the processends.

(b) Repetition Interleaving Process

FIG. 14 is a flowchart illustrating an example of a schematic flow of arepetition interleaving process related to the first technique accordingto the second embodiment.

The interleaving unit 153 interleaves a partial sequence (0-th to K−1-thbits) which has the length K in the bit sequence of the informationblock using the interleaver which has the selected length K (that is,the selected interleaver) (S441). The interleaver is an interleaverunique to a user.

The interleaving unit 153 concatenates a sequence obtained byinterleaving the partial sequence with a remaining sequence (K-th toM−1-th bits) in the bit sequence (S443).

Furthermore, the interleaving unit 153 interleaves a partial sequence(M-K-th to M−1-th bits) which has the length K in the concatenated bitsequence using the interleaver which has the selected length K (S445).

The interleaving unit 153 concatenates a remaining sequence (0-th toM-K−1-th bits) of the concatenated bit sequence with a sequence obtainedby interleaving the partial sequence (S447). Then, the process ends.

(4) De-Interleaving

Also, the second radio communication apparatus 200 performsde-interleaving corresponding to the above-described interleaving in thefirst radio communication apparatus 100.

Referring back to FIG. 12 , for example, when it is assumed that the bitsequence 47 is a received bit sequence, the length K according to thelength M of the bit sequence 47 is selected from the plurality ofpredetermined lengths and a de-interleaver which has the length K isused. That is, a de-interleaver which has the length K is selected. Thede-interleaver corresponds to an interleaver which has the length K andis unique to a user. First, the partial sequence 45 which has the lengthK in the received bit sequence 47 is de-interleaved using thede-interleaver. As a result, the sequence 43 is obtained. Then, theremaining sequence 41 in the received bit sequence 47 is concatenatedwith the sequence 43. Furthermore, the partial sequence 37 which has thelength K in the concatenated bit sequence is de-interleaved using thede-interleaver. As a result, the sequence 33 is obtained. Then, thesequence 33 is concatenated with the remaining sequence 35 in theconcatenated bit sequence to obtain the de-interleaved bit sequence 31.

5.3. Second Technique of Interleaving

Next, a second technique of the interleaving according to the secondembodiment will be described with reference to FIGS. 15 to 17 .

(1) Length/Interleaver

In the second technique, an interleaver which has one predeterminedlength K is used to interleave the bit sequence.

Also, the bit sequence is a bit sequence of an information blockgenerated from transmission data for a user. The interleaver is aninterleaver unique to the user. For example, the predetermined length K(the length of the interleaver) is a length of a power of two. Forexample, the interleaver is a DI.

(2) Interleaving

In the second technique, the interleaving unit 153 first interleaves oneor more partial sequences which have the predetermined length K and areincluded in the bit sequence using the interleaver.

Specifically, for example, the number N of partial sequences which havethe predetermined length K and are included in the bit sequence whichhas the length M is calculated as follows, and the number of partialsequences is interleaved using the interleaver.

$\begin{matrix}{N = {{floor}\left( \frac{M}{K} \right)}} & \left\lbrack {{Math}.4} \right\rbrack\end{matrix}$

Thereafter, the N sequences obtained through the interleaving areconcatenated.

When the length M is a K multiple of the predetermined length K, theconcatenated sequence including N sequences is output as an interleavedbit sequence. Conversely, when the length M is not a multiple of thepredetermined length K, the interleaving unit 153 performs newinterleaving (repetition interleaving). In particular, the interleavingunit 153 interleaves a part of the bit sequence repeatedly. Hereinafter,a specific example will be described with reference to FIG. 15 .

FIG. 15 is an explanatory diagram illustrating an example of the secondtechnique of the interleaving according to the second embodiment.Referring to FIG. 15 , a bit sequence 51 which has a length M isillustrated. In this case, the number N of partial sequences 53 whichhas the predetermined length K and is included in the bit sequence 51 iscalculated. Then, N partial sequences 53 (partial sequences 53A and 53Band the like) are interleaved using the interleaver which has thepredetermined length K. As a result, N sequences 57 (sequences 57A and57B and the like) are obtained. Then, the N sequences 57 areconcatenated to obtain a sequence 59. In this example, the length M isnot a multiple of the length K. Therefore, the sequence 59 is furtherconcatenated with a remaining sequence 55 (K*N-th to M−1-th bits) in thebit sequence 51. Then, a partial sequence 65 (M-K-th to M−1-th bits)which has the length K in the further concatenated bit sequence isinterleaved using the interleaver which has the predetermined length K.The partial sequence 65 includes a sequence 61 in the sequence 59 andthe remaining sequence 55. Then, a remaining sequence 63 (0-th toM-K−1-th bits) in the sequence 59 is concatenated with a sequence 67obtained by interleaving the partial sequence 65 to obtain aninterleaved bit sequence 69.

(3) Flow of Process (a) Overall Flow

FIG. 16 is a flowchart illustrating an example of a schematic flow of aprocess related to the second technique according to the secondembodiment.

The information acquisition unit 151 acquires the information block (forexample, a codeword) generated from transmission data (for example, atransport block) for a user and subjected to error correction coding(S451).

The interleaving unit 153 calculates the number N of partial sequenceswhich have the predetermined length K and are included in the bitsequence of the information block (S453).

The interleaving unit 153 interleaves the N partial sequences includedin the bit sequence using the interleaver which has the predeterminedlength K (S455).

The interleaving unit 153 concatenates the N sequences obtained byinterleaving the N partial sequences (S457).

When the length M of the bit sequence of the information block is amultiple of the predetermined length K (YES in S459), the process ends.

Otherwise (NO in S459), the interleaving unit 153 performs a repetitioninterleaving process (S460). Then, the process ends.

(b) Repetition Interleaving Process

FIG. 17 is a flowchart illustrating an example of a schematic flow of arepetition interleaving process related to the second techniqueaccording to the second embodiment.

The interleaving unit 153 further concatenates the concatenated sequencewith the remaining sequence (K*N-th to M−1-th bits) in the bit sequenceof the information block (S461).

The interleaving unit 153 interleaves the partial sequence (M-K-th toM−1-th bits) in the further concatenated bit sequence using theinterleaver which has the predetermined length K (S463).

The interleaving unit 153 concatenates the remaining bit sequence (0-thto M-K−1-th bits) in the further concatenated bit sequence with thesequence obtained by interleaving the partial sequence (S465). Then, theprocess ends.

(4) De-Interleaving

Also, the second radio communication apparatus 200 performsde-interleaving corresponding to the above-described interleaving in thefirst radio communication apparatus 100.

Referring back to FIG. 15 , for example, when it is assumed that the bitsequence 69 is the received bit sequence, the partial sequence 67 thathas the predetermined length K in the received bit sequence 69 is firstde-interleaved using a de-interleaver (a de-interleaver corresponding tothe interleaver unique to the user) which has the predetermined lengthK. As a result, the sequence 65 is obtained. Then, the remainingsequence 63 in the received bit sequence 69 is concatenated with thesequence 65. Furthermore, the plurality of partial sequences 57 whichhave the predetermined length K in the concatenated bit sequence arede-interleaved using the de-interleaver which has the predeterminedlength K. As a result, the plurality of sequences 53 are obtained. Then,the plurality of sequences 53 and the sequence 55 are concatenated toobtain the de-interleaved bit sequence 51.

5.4. Variations of Interleaving

Next, variations of the interleaving according to the second embodimentwill be described with reference to FIG. 18 .

As the examples of the first and second techniques described above, theexamples in which the bit sequence of the information block isinterleaved using one interleaver have been described, but the secondembodiment is not limited to the examples. The bit sequence may beinterleaved using two or more interleavers.

Further, as the examples of the first and second techniques describedabove, the examples in which the number of regions interleaved twice ormore is 1 have been described, but the second embodiment is not limitedto the examples. The number of regions to be interleaved twice or moremay be 2 or more.

FIG. 18 is an explanatory diagram illustrating another example of theinterleaving according to the second embodiment. Referring to FIG. 18 ,a bit sequence of M bits is illustrated. In this example, the bitsequence is interleaved using interleavers I₀, I₁, I₂, and I₃ which havelengths of K₀ bits, K₁ bits, K₂ bits, and K₃ bits. Furthermore, in thisexample, a part of the sequence generated by performing interleavingusing the interleaver I₀ is interleaved using the interleaver I₁.Similarly, a part of the sequence generated by performing interleavingusing the interleaver I₁ is interleaved using the interleaver I₂ and apart of the sequence generated by performing interleaving using theinterleaver I₂ is interleaved using the interleaver I₃.

5.5. Technical Features (1) Interleaving

As described above, in the second embodiment, the informationacquisition unit 151 acquires the information block generated from thetransmission data for the user and subjected to the error correctioncoding. The interleaving unit 153 interleaves the bit sequence of theinformation block using the interleaver unique to the user. Inparticular, the interleaving unit 153 interleaves the bit sequence byinterleaving the two or more partial sequences obtained from the bitsequence.

Furthermore, in the second embodiment, at least one of the two or morepartial sequences includes a part of the sequence obtained byinterleaving the other of the two or more partial sequences. That is, atleast a part of the bit sequence is interleaved repeatedly.

(a) Transmission Data

The first radio communication apparatus 100 may be a base station andthe transmission data may be transmission data destined for the user.Alternatively, the first radio communication apparatus 100 may be aterminal apparatus of the user and the transmission data may betransmission data from the user.

For example, the transmission data is a transport block.

(b) Information Block

For example, the information block is a codeword. Alternatively, as inthe fourth embodiment to be described below, the information block mayalso be a code block.

(c) Bit Sequence of Information Block

For example, the bit sequence of the information block has a lengthwhich is not a power of two.

(d) Partial Sequences

As described above, at least one of the two or more partial sequencesincludes a part of the sequence obtained by interleaving the other ofthe two or more partial sequences. That is, at least a part of the bitsequence is interleaved repeatedly.

For example, the at least one of the partial sequences further includesa part of the bit sequence.

For example, a total sum of the lengths of the two or more partialsequences is greater than the length of the bit sequence. For example,each of the two or more partial sequences has a length of a power oftwo. For example, the two or more partial sequences have the samelength.

Referring back to FIG. 12 , the two or more partial sequences arepartial sequences 33 and 43. The partial sequence 43 includes a part(sequence 39) of the sequence 37 obtained by interleaving the partialsequence 33. The partial sequence 43 further includes a part (sequence35) of the bit sequence 31. A total sum of the lengths of the partialsequences 33 and 43 is greater than the length of the bit sequence 31.The partial sequences 33 and 43 have the same length as a power of two.

Referring back to FIG. 15 , the two or more partial sequences are theplurality of partial sequences 53 and 65. The partial sequence 65includes a part (sequence 61) of the sequence 57B obtained byinterleaving the partial sequence 53B. The partial sequence 65 furtherincludes a part (sequence 55) of the bit sequence 51. A total sum of thelengths of the plurality of partial sequences 53 and 65 is greater thanthe length of the bit sequence 51. The plurality of partial sequences 53and 65 have the same length as a power of two.

(e) Interleaving

For example, the interleaving unit 153 interleaves each of the two ormore partial sequences using the corresponding interleaver.

(e-1) Interleaver

For example, the corresponding interleaver is an interleaver which hasthe same length as the length of the partial sequence and is unique tothe user. Furthermore, the corresponding interleaver may be aninterleaver unique to the transmission data (for example, a transportblock) or the information block (for example, a codeword or a codeblock).

For example, the corresponding interleaver is an interleaver which canbe generated in each of a transmitter and a receiver (in other words, aninterleaver which can be generated based on a calculation equation). Forexample, the corresponding interleaver is a DI. In this case, thecorresponding interleaver may be referred to as an overlappeddeterministic interleaver (ODI). As another example, the correspondinginterleaver may be an LCI. In this case, the corresponding interleavermay be referred to as an overlapped linear congruential interleaver(OLCI). Also, the corresponding interleaver is not limited to theexamples.

The corresponding interleaver may also be mounted as hardware (forexample, programmable hardware) or may also be mounted as software. Aninterleave pattern of the corresponding interleaver may be replaceable.

(e-2) First Technique

For example, the length of each of the two or more partial sequences isa length according to the length of the bit sequence among the pluralityof predetermined lengths.

Furthermore, specifically, for example, the length of at least one ofthe two or more partial sequences is a maximum length among one or morelengths equal to or less than the length of the bit sequence andincluded in the plurality of predetermined lengths.

Referring back to FIG. 12 , the two or more partial sequences are thepartial sequences 33 and 43. The length of each of the partial sequences33 and 43 is a length according to the length of the bit sequence 31among the plurality of predetermined lengths. More specifically, thelength of each of the partial sequences 33 and 43 is a maximum lengthamong one or more lengths equal to or less than the length of the bitsequence 31 and included in the plurality of predetermined lengths. Forexample, the plurality of predetermined lengths are 128 bits, 256 bits,512 bits, 1024 bits, 2048 bits, and 4096 bits. The length of the bitsequence 31 is 1632 bits. In this case, each of the partial sequences 33and 43 is 1024 bits.

(e-3) Second Technique

For example, the length of each of the two or more partial sequences isone predetermined length.

Referring back to FIG. 15 , the two or more partial sequences are theplurality of partial sequences 53 and 65. The length of each of theplurality of partial sequences 53 and 65 is one predetermined length.

As described above, the interleaving unit 153 interleaves the bitsequence of the information block. Thus, for example, it is possible totransmit data more flexibly and with a lesser burden in the IDMA system.

More specifically, for example, in the IDMA system, it is possible totransmit a bit sequence which has any length without transmitting andreceiving interleavers between a transmission side and a reception side.For example, since the interleaver may not be transmitted and receivedbetween the transmitter and the receiver, a large memory is notnecessary in the transmitter and additional radio resources are notnecessary either. Therefore, it is possible to reduce a burden on thetransmitter and the system. Further, since the length of the bitsequence of the information block is not limited to a power of two, itis possible to transmit data more flexibly.

Also, in the second embodiment, since a lower limit of the length of thepartial sequence (the length of the interleaver) is provided, it ispossible to avoid a situation in which the length of the partialsequence (the length of the interleaver) is considerably shortened.Therefore, the performance of BER/BLER can be more preferable.

In particular, according to the first technique, by using an interleavercloser to the length of the bit sequence of the information block, it ispossible to distribute bits more satisfactorily. Therefore, theperformance of BER/BLER can be more preferable.

In particular, according to the second technique, it is not necessary toselect the length of the partial sequence (the length of theinterleaver) according to the length of the bit sequence of theinformation block. Therefore, it is possible to perform the interleavingmore rapidly.

(2) De-Interleaver

The information acquisition unit 251 acquires the received bit sequence.The de-interleaving unit 253 generates the bit sequence of theinformation block not subjected to error correction decoding byde-interleaving the received bit sequence using the de-interleavercorresponding to the interleaver unique to the user. In particular, thede-interleaving unit 253 de-interleaves the received bit sequence byde-interleaving two or more partial sequences obtained from the receivedbit sequence.

Furthermore, in the second embodiment, at least one of the two or morepartial sequences includes a part of the sequence obtained byde-interleaving the other of the two or more partial sequences. That is,at least a part of the received bit sequence is de-interleavedrepeatedly.

(a) Information Block

For example, the information block is a codeword. Alternatively, as inthe fourth embodiment to be described below, the information block mayalso be a code block.

(b) Received Bit Sequence

For example, the received bit sequence is a sequence received in asubframe. For example, the received bit sequence is a sequence after ESEand de layer mapping. For example, the received bit sequence has alength which is not a power of two.

(c) Partial Sequences

As described above, at least one of the two or more partial sequencesincludes a part of the sequence obtained by de-interleaving the other ofthe two or more partial sequences. For example, the at least one of thepartial sequences further includes a part of the received bit sequence.

For example, a total sum of the lengths of the two or more partialsequences is greater than the length of the received bit sequence.

(d) De-Interleaving

For example, the de-interleaving unit 253 de-interleaves each of the twoor more partial sequences using the corresponding de-interleaver.

(d-1) De-Interleaver

For example, the corresponding de-interleaver is a de-interleaver whichhas the same length as the length of the partial sequence and is ade-interleaver corresponding to the interleaver unique to the user.

For example, the interleaver unique to the user is an interleaver whichcan be generated in each of a transmitter and a receiver (in otherwords, an interleaver which can be generated based on a calculationequation). For example, the interleaver unique to the user is a DI. Asanother example, the interleaver unique to the user may be an LCI. Also,the interleaver unique to the user is not limited to the examples.

The corresponding interleaver may also be mounted as hardware (forexample, programmable hardware) or may also be mounted as software. Ade-interleave pattern of the corresponding de-interleaver may bereplaceable.

(d-2) First Technique

For example, the length of each of the two or more partial sequences isa length according to the length of the received bit sequence among theplurality of predetermined lengths.

Furthermore, specifically, for example, the length of at least one ofthe two or more partial sequences is a maximum length among one or morelengths equal to or less than the length of the received bit sequenceand included in the plurality of predetermined lengths.

Referring back to FIG. 12 , for example, the de-interleaving unit 253de-interleaves the partial sequences 45 and 37 which have the length Kusing the de-interleaver which has the length K according to the lengthM of the received bit sequence 47. As a result, the bit sequence 31 canbe obtained.

(d-3) Second Technique

For example, the length of each of the two or more partial sequences isone predetermined length.

Referring back to FIG. 15 , for example, the de-interleaving unit 253de-interleaves the partial sequence 67 and the plurality of partialsequences 57 which have the predetermined length K using thede-interleaver which has the predetermined length K. As a result, thebit sequence 51 can be obtained.

6. Third Embodiment

Next, a third embodiment of the present disclosure will be describedwith reference to FIGS. 19 to 21 .

6.1. Overview (1) Technical Problem

A technical problem according to the third embodiment is the same as thetechnical problem according to the first embodiment. Accordingly, therepeated description thereof will be omitted here.

(2) Technical Means

In the third embodiment, the information acquisition unit 151 acquiresan information block generated from transmission data for a user andsubjected to error correction coding. The interleaving unit 153interleaves the bit sequence using another interleaver obtained from theinterleaver longer than the bit sequence of the information block andunique to the user or the interleaver unique to the user.

Thus, for example, it is possible to transmit data more flexibly andwith a lesser burden in the IDMA system. More specifically, for example,a bit sequence which has any length can be transmitted withouttransmitting and receiving an interleaver between the transmission sideand the reception side in the IDMA system.

6.2. Example of Interleaving

Next, an example of interleaving according to the third embodiment willbe described with reference to FIGS. 19 to 21 .

(1) Interleaver

When the length M of the bit sequence of the information block (forexample, a codeword) generated from the transmission data for the useris a length of a power of two, the bit sequence is interleaved using theinterleaver which has the length M and is unique to the user. Forexample, the interleaver is a DI.

Conversely, in particular, when the length M of the bit sequence is notthe length of the power of two, the interleaver longer than the length Mand unique to the user is acquired. For example, the interleaver is aminimum interleaver longer than the length M among the interleaverswhich have lengths of powers of two. For example, the interleaver is aDI. Furthermore, another interleaver which has the length M is generatedfrom the interleaver. Hereinafter, a specific example will be describedwith reference to FIG. 19 .

FIG. 19 is an explanatory diagram illustrating an example of aninterleaver according to the third embodiment. Referring to FIG. 19 , abit sequence 71 of 1632 bits is illustrated. Here, 1632 bits is longerthan 1024 (=2¹⁰) and shorter than 2048 (=2¹¹). Accordingly, aninterleaver 81 which has a length of 2048 (=2¹¹) bits and is unique to auser is acquired. Furthermore, an interleaver 85 which has a length of1632 bits is generated from the interleaver. Specifically, for example,a portion in which input bits are output to bits not included in anoutput bit sequence of 1632 bits in the interleaver 81 is excluded. Onthe other hand, a portion in which input bits are output to bitsincluded in the output bit sequence of 1632 bits in the interleaver 81remains. Specifically, for example, a portion 83 or the like in theinterleaver 81 is excluded. Thus, an interleaver 85 which has a lengthof 1632 bits is generated.

(2) Interleaving

For example, the interleaving unit 153 interleaves the bit sequence (forexample, the bit sequence 71) using the other interleaver (for example,the interleaver 85) which has the length M.

Also, the interleaver (for example, the interleaver 81) longer than thelength M may be used instead of using the other interleaver (forexample, the interleaver 85) which has the length M. For example, theinterleaving unit 153 may interleave the bit sequence not using theportion in which the input bits are output to the bits not included inthe output bit sequence in the interleaver longer than the length M butusing only the other portion.

(3) Flow of Process (a) Overall Flow

FIG. 20 is a flowchart illustrating an example of a schematic flow of aprocess according to the third embodiment.

The information acquisition unit 151 acquires the information block (forexample, a codeword) generated from transmission data (for example, atransport block) for a user and subjected to error correction coding(S471).

When the length of the bit sequence of the information block is not thelength of a power of two (NO in S473), the interleaving unit 153acquires the interleaver longer than the bit sequence and unique to theuser (S475). Then, the interleaving unit 153 performs an interleavergeneration process (S490) and interleaves the bit sequence of theinformation block using the generated interleaver (S477). Then, theprocess ends.

Conversely, when the length of the bit sequence of the information blockis the length of the power of two (YES in S473), the interleaving unit153 acquires the interleaver which has the same length as the length ofthe bit sequence and is unique to the user (S479). Then, theinterleaving unit 153 interleaves the bit sequence of the informationblock using the interleaver (S481). Then, the process ends.

(b) Interleaver Generation Process

FIG. 21 is a flowchart illustrating an example of a schematic flow ofthe interleaver generation process according to the third embodiment.

First, indexes i and j are initialized to 0 (S491).

When a value I_(EXTEND)(i) of the interleaver longer than the bitsequence is less than the length M of the bit sequence (YES in S493),the value I_(EXTEND)(i) is applied as a value I_(M)(j) of theinterleaver which has the length M (S495). Then, the index j isincreased (S496) and the index i is also increased (S497).

When I_(EXTEND)(i) is equal to or greater than the length M of the bitsequence (NO in S493), the index i is increased (S497).

When the index i is less than K (YES in S499), the process returns tostep S491. Otherwise (NO in S499), the process ends.

(4) De-Interleaving

Also, the second radio communication apparatus 200 performsde-interleaving corresponding to the above-described interleaving in thefirst radio communication apparatus 100.

Referring back to FIG. 19 , for example, the de-interleaving unit 253de-interleaves the received bit sequence of 1632 bits using thede-interleaver corresponding to the interleaver 85. As a result, the bitsequence 71 can be obtained.

6.3. Technical Features (1) Interleaving

As described above, in the third embodiment, the information acquisitionunit 151 acquires the information block generated from the transmissiondata for the user and subjected to the error correction coding. Theinterleaving unit 153 interleaves the bit sequence using anotherinterleaver obtained from the interleaver longer than the bit sequenceof the information block and unique to the user or the interleaverunique to the user.

(a) Transmission Data

The first radio communication apparatus 100 may also be a base stationand the transmission data may also be transmission data destined for theuser. Alternatively, the first radio communication apparatus 100 mayalso be a terminal apparatus of the user and the transmission data maybe transmission data from the user.

For example, the transmission data is a transport block.

(b) Information Block

For example, the information block is a codeword. Alternatively, as inthe fourth embodiment to be described below, the information block mayalso be a code block.

(c) Bit Sequence of Information Block

For example, the bit sequence of the information block has a lengthwhich is not a power of two.

Referring back to FIG. 19 , for example, the bit sequence is the bitsequence 71 and has a length of 1632 bits.

(d) Interleaver (d-1) Interleaver Longer than Bit Sequence and Unique toUser

For example, the interleaver longer than the bit sequence and unique tothe user is an interleaver which has a length of a power of two.Furthermore, the interleaver may be an interleaver unique to thetransmission data (for example, a transport block) or the informationblock (for example, a codeword or a code block).

For example, the interleaver unique to the user is an interleaver whichcan be generated in each of a transmitter and a receiver (in otherwords, an interleaver which can be generated based on a calculationequation). For example, the interleaver unique to the user is a DI. Asanother example, the interleaver unique to the user may be an LCI. Also,the interleaver unique to the user is not limited to the examples.

Referring back to FIG. 19 , for example, the interleaver unique to theuser is the interleaver 81.

(d-2) Another Interleaver

For example, the other interleaver is an interleaver which has the samelength as the length of the bit sequence of the information block.

Furthermore, for example, the other interleaver is an interleaverobtained by excluding a portion in which input bits are output to bitsnot included in an output bit sequence which has the same length as thelength of the bit sequence from the interleaver unique to the user.

Referring back to FIG. 19 , for example, the other interleaver is theinterleaver 85. As described above, the interleaver 85 is obtained byexcluding the portion (the portion 83 or the like) in which input bitsare output to bits not included in an output bit sequence of 1632 bitsfrom the interleaver 81.

(e) Interleaving

As described above, for example, the interleaving unit 153 interleavesthe bit sequence using the other interleaver.

Referring back to FIG. 19 , for example, the interleaving unit 153interleaves the bit sequence 71 using the interleaver 85.

Also, the interleaving unit 153 may interleave the bit sequence usingthe interleaver unique to the user. In this case, the interleaving unit153 may interleave the bit sequence not using the portion in which theinput bits are output to the bits not included in the output bitsequence in the interleaver unique to the user but using only anotherportion.

As described above, the interleaving unit 153 interleaves the bitsequence of the information block. Thus, for example, it is possible totransmit data more flexibly and with a lesser burden in the IDMA system.

More specifically, for example, in the IDMA system, it is possible totransmit a bit sequence which has any length without transmitting andreceiving interleavers between a transmission side and a reception side.For example, since the interleaver may not be transmitted and receivedbetween the transmitter and the receiver, a large memory is notnecessary in the transmitter and additional radio resources are notnecessary either. Therefore, it is possible to reduce a burden on thetransmitter and the system. Further, since the length of the bitsequence of the information block is not limited to a power of two, itis possible to transmit data more flexibly.

Also, in the third embodiment, for example, since the interleaver whichhas the same length as the length of the bit sequence of the informationblock is used, it is possible to distribute bits more satisfactorily.Therefore, the performance of BER/BLER can be more preferable.

(2) De-Interleaving

The information acquisition unit 251 acquires a received bit sequence.The de-interleaving unit 253 generates a bit sequence of the informationblock not subjected to error correction decoding by de-interleaving thereceived bit sequence using a de-interleaver corresponding to anotherinterleaver obtained from the interleaver longer than the received bitsequence and unique to a user.

(a) Information Block

For example, the information block is a codeword. Alternatively, as inthe fourth embodiment to be described below, the information block mayalso be a code block.

(b) Received Bit Sequence

For example, the received bit sequence is a sequence received in asubframe. For example, the received bit sequence is a sequence after ESEand de layer mapping. For example, the received bit sequence has alength which is not a power of two.

(c) De-Interleaver (c-1) Interleaver

For example, the interleaver longer than the received bit sequence andunique to the user is an interleaver which has a length of a power oftwo. For example, the other interleaver is an interleaver which has thesame length as the length of the bit sequence of the information block.The description of the interleaver is the same as the above description.Accordingly, the repeated description thereof will be omitted here.

(c-2) De-Interleaver

Referring back to FIG. 19 , for example, the de-interleavercorresponding to the other interleaver is a de-interleaver correspondingto the interleaver 85.

(d) De-Interleaver

As described with reference to FIG. 19 , for example, the interleavingunit 153 interleaves the received bit sequence of 1632 bits using thede-interleaver corresponding to the interleaver 85. As a result, the bitsequence 71 can be obtained.

7. Fourth Embodiment

Next, a fourth embodiment of the present disclosure will be describedwith reference to FIGS. 22 to 26 .

7.1. Overview (1) Technical Problem

For example, in an IDMA system, a bit sequence of a codeword isinterleaved using an interleaver unique to a user. The length of thecodeword is one length in a broad range.

However, in the IDMA system, when a range of the length of a bitsequence which is an interleaving target is broad, a situation notpreferable in regard to interleaving of the bit sequence can occur.

As one example, in accordance with the technique of the firstembodiment, the first technique of the second embodiment, or thetechnique of the third embodiment, interleavers which have variouslengths can be prepared to interleave the bit sequence. Therefore, aburden on a transmitter and a receiver can increase.

As another example, when the bit sequence is interleaved in accordancewith the second technique of the second embodiment, the length of thebit sequence can increase considerably compared to an interleaver whichhas a predetermined length. As a result, when the interleaver is used,bits of the bit sequence are spread locally, but are not spread overall.As a result, the performance of BER/BLER may deteriorate.

Accordingly, it is preferable to provide a structure that makes itpossible to further narrow a range of the length of a bit sequence whichis an interleaving target in the IDMA system.

(2) Technical Means

In the fourth embodiment, the information acquisition unit 151 acquiresan information block generated from transmission data for a user. Theinterleaving unit 153 interleaves a bit sequence of the informationblock using an interleaver unique to the user. In particular, theinformation block is a block after segmentation for error correctioncoding and the error correction coding and before integration after theerror correction coding. For example, the information block is a codeblock.

Thus, for example, it is possible to further narrow the range of thelength of the bit sequence which is the interleaving target in the IDMAsystem.

7.2. Example of Interleaving

Next, an example of interleaving according to the third embodiment willbe described with reference to FIGS. 22 to 26 .

(1) Interleaving

For example, in a system such as LTE, a plurality of code blocks areconcatenated to generate one codeword.

In particular, in this example, not a codeword but one or more codeblocks are interleaved using an interleaver unique to a user. Forexample, two or more code blocks are interleaved in parallel. Forexample, the interleaver is a DI and can be referred to as a code blockparallel deterministic interleaver (CBPDI). The interleaver may befurther unique to a cell, a codeword (or a transport block), a codeblock, or a link direction. Hereinafter, a specific example will bedescribed with reference to FIG. 22 .

FIG. 22 is an explanatory diagram illustrating an example ofinterleaving according to a fourth embodiment. Referring to FIG. 22 , asdescribed with reference to FIG. 3 , after a transport block for a useris generated, the addition of CRC (S303), the code block segmentation(S305), the code block forward error correction (FEC) encoding (S307)which is channel coding, the rate matching (S309), the code blockconcatenation (S311), and the like are performed. In particular, in thisexample, after the code block segmentation (S305), the code block FECencoding (S307), and the rate matching (S309) and before the code blockconcatenation (S311), the code blocks are interleaved using theinterleaver unique to the user. For example, three code blockscorresponding to the same transport block are interleaved using the sameinterleaver.

Also, as in the example of FIG. 22 , when the codeword is interleaved,for example, the interleaving (S313) of the codeword described withreference to FIG. 3 is not performed.

Further, for example, to match the lengths of the code blocks which areinterleaving targets, bit padding or bit filtering for the transportblock can be performed before the code block segmentation (S305).Alternatively, the bit padding or the bit filtering for the code blockscan be performed between the code block segmentation (S305) and the codeblock FEC encoding (S307).

(2) Concatenation/Bit Collection (a) Concatenation

For example, two or more code blocks to be interleaved are concatenatedto generate a codeword.

(a-1) First Example

As a first example, c(i) which is the value of an i-th bit of an outputsequence is expressed as follows.

$\begin{matrix}{{c(i)} = {b_{i{mod}{}N_{CB}}\left( {{floor}\left( \frac{i}{N_{CB}} \right)} \right)}} & \left\lbrack {{Math}.5} \right\rbrack\end{matrix}$

N_(CB) is the number of code blocks. Further, b_(j)(k) is the value of ak-th bit in a bit sequence of a j-th code block. An index i is in therange of 0 to L_(CB)*N_(CB)−1 and L_(CB) is the length of a code block.Hereinafter, a specific example will be described with reference to FIG.23 .

FIG. 23 is an explanatory diagram illustrating the first example of codeblock concatenation according to the fourth embodiment. Referring toFIG. 23 , sequences of three code blocks (code blocks 0, 1, and 2) areillustrated. The sequences of the three code blocks are concatenated togenerate a codeword. In the codeword, three bit sets including bits ofcode blocks 0, 1, and 2 are disposed in order. That is, in the codeword,the three bit sets including b₀(k), b₁(k), and b₂(k) are disposed inorder of the index k. The index k is in the range of 0 to L_(CB)−1.

(a-2) Second Example

As a second example, an output sequence c(i) may be expressed asfollows.

$\begin{matrix}{{c(i)} = {b_{{floor}(\frac{i}{L_{CB}})}\left( {i{mod}L_{CB}} \right)}} & \left\lbrack {{Math}.6} \right\rbrack\end{matrix}$

As described above, b_(j)(k) is the value of a k-th bit in a bitsequence of a j-th code block. L_(CB) is the length of a code block. Theindex i is in the range of 0 to L_(CB)*N_(CB)−1. L_(CB) is the number ofcode blocks. Hereinafter, a specific example will be described withreference to FIG. 24 .

FIG. 24 is an explanatory diagram illustrating the second example of thecode block concatenation according to the fourth embodiment. Referringto FIG. 24 , sequences of three code block (code blocks 0, 1, and 2) areillustrated. The three code blocks are concatenated to generate acodeword. In the codeword, code blocks 0, 1, and 2 are disposed inorder.

(b) Bit Collection

Bit collection may be performed on the interleaved two or more codeblocks. As a result, a codeword may be generated. The bit collection maybe bit collection of exclusive OR (XOR). In this case, c(i) which is thevalue of an i-th bit of an output sequence may be expressed as follows.

$\begin{matrix}{{c(i)} = {\underset{j = 0}{\overset{N_{CB} - 1}{\oplus}}\left( {b_{j}(i)} \right)}} & \left\lbrack {{Math}.7} \right\rbrack\end{matrix}$

Here, b_(j)(i) is the value of an i-th bit in the bit sequence of a j-thcode block. N_(CB) is the number of code blocks. The index i is in therange of 0 to N_(CB)−1 and L_(CB) is the length of a code block.Hereinafter, a specific example will be described with reference to FIG.25 .

FIG. 25 is an explanatory diagram illustrating a bit collection exampleof a code block according to the fourth embodiment. Referring to FIG. 25, three code blocks (code blocks 0, 1, and 2) are illustrated. In thisexample, bit collection is performed by calculating XOR of the threecode blocks. As a result, a sequence which has the same length as thelength of the sequence of each code block is output.

(3) Flow of Process

FIG. 26 is a flowchart illustrating an example of a schematic flow of aprocess according to the fourth embodiment.

The information acquisition unit 151 acquires an information blockgenerated from transmission data (for example, a transport block) for auser (S511). The information block is a block (for example, a codeblock) after segmentation for error correction coding and the errorcorrection coding and before integration (for example, concatenation orbit collection) after the error correction coding.

The interleaving unit 153 interleaves a bit sequence of the informationblock using the interleaver unique to the user (S513). Then, the processends.

(4) De-Interleaving

Also, the second radio communication apparatus 200 performsde-interleaving corresponding to the above-described interleaving in thefirst radio communication apparatus 100.

For example, the de-interleaving unit 253 de-interleaves a received bitsequence using a de-interleaver corresponding to an interleaver uniqueto a user. For example, the received bit sequence is a bit sequence of acode block before error correction decoding. As a result of thede-interleaving on the received bit sequence, a bit sequence of the codeblock before the error correction decoding is generated.

7.3. Technical Features (1) Interleaving

As described above, in the fourth embodiment, the informationacquisition unit 151 acquires an information block generated fromtransmission data for a user. The interleaving unit 153 interleaves abit sequence of the information block using an interleaver unique to theuser. In particular, the information block is a block after segmentationfor error correction coding and the error correction coding and beforeintegration after the error correction coding.

(a) Transmission Data

The first radio communication apparatus 100 may also be a base stationand the transmission data may also be transmission data destined for theuser. Alternatively, the first radio communication apparatus 100 mayalso be a terminal apparatus of the user and the transmission data maybe transmission data from the user.

For example, the transmission data is a transport block.

(b) Information Block

For example, the information block is a code block. For example, thesegmentation for the error correction coding is code block segmentation.For example, the integration after the error correction coding isconcatenation or bit collection of exclusive OR. For example, theconcatenation is code block concatenation.

(c) Interleaving (c-1) Interleaver

For example, the interleaver unique to the user is an interleaver whichhas a length of a power of two.

For example, the interleaver unique to the user is an interleaver whichcan be generated in each of a transmitter and a receiver (in otherwords, an interleaver which can be generated based on a calculationequation). For example, the interleaver unique to the user is a DI. Asanother example, the interleaver unique to the user may be an LCI. Also,the interleaver unique to the user is not limited to the examples.

The interleaver unique to the user may be an interleaver unique to acell, a unit block larger than the information block, or a linkdirection. The unit block may be the transmission data (for example, atransport block) or may be a codeword. Alternatively, the interleavermay be an interleaver which is not unique to the unit block and isunique to the information block (for example, a code block).

(c-2) Information Block Corresponding to Same Unit Block

For example, the interleaving unit 153 interleaves bit sequences of twoor more information blocks (for example, two or more code blocks)corresponding to the same unit block (for example, the same transportblock or the same codeword) using the same interleaver. Alternatively,the interleaving unit 153 may interleave a bit sequence of aninformation block (for example, a code block) using an interleaverunique to the information block.

For example, the same unit block is the same transport block or the samecodeword.

Referring back to FIG. 22 , for example, the interleaving unit 153interleaves three codewords using the same interleaver unique to a user.

As described above, the interleaving unit 153 interleaves the bitsequence of the information block. Thus, for example, it is possible tofurther narrow the range of the length of the bit sequence which is theinterleaving target in the IDMA system. More specifically, for example,the bit sequence which is an interleaving target is not a bit sequenceof a codeword but a bit sequence of a code block, and a range of thelength of the bit sequence which is an interleaving target is narrowed.

Also, in the fourth embodiment, for example, a process (for example, MUDand ESE) on a reception side can be performed in a code block unitrather than a codeword unit. As a result, it is possible to decreaselatency of demodulation, decoding, and the like.

(2) De-Interleaving

The information acquisition unit 251 acquires a received bit sequence.The de-interleaving unit 253 generates a bit sequence of an informationblock by de-interleaving the received bit sequence using ade-interleaver corresponding to an interleaver unique to a user. Theinformation block is a block after segmentation for error correctiondecoding and before the error correction decoding.

(a) Information Block

For example, the information block is a code block. For example, thesegmentation for the error correction decoding is code blockdeconcatenation.

(b) Received Bit Sequence

For example, the received bit sequence is a sequence received in asubframe. For example, the received bit sequence is a sequence aftersegmentation for error correction decoding (for example, code blockdeconcatenation) and before the error correction decoding.

(c) De-Interleaving (c-1) De-Interleaver

For example, the interleaver unique to the user is an interleaver whichhas a length of a power of two. The description of the interleaver isthe same as the above description. Accordingly, the repeated descriptionthereof will be omitted here.

For example, the de-interleaver also has a length of a power of two.

(c-2) Information Block Corresponding to Same Unit Block

For example, the de-interleaving unit 253 interleaves two or morereceived bit sequences corresponding to the same unit block using thesame de-interleaver.

For example, the same unit block is the same transport block or the samecodeword.

The fourth embodiment has been described above. The technical featuresaccording to the fourth embodiment may also be applied to the first tothird embodiments.

8. Fifth Embodiment

Next, a fifth embodiment of the present disclosure will be described.

8.1. Overview (1) Technical Problem

For example, in the IDMA system, a bit sequence is interleaved using aninterleaver unique to a user. As the interleaver, there is aninterleaver which can be generated in each of a transmitter and areceiver (in other words, an interleaver which can be generated based ona calculation equation). For example, the interleaver is a DI.

However, even when a DI is an interleaver unique to any user, the firstbit in an input bit sequence is output as the first bit in an output bitsequence. As a result, BLER can deteriorate.

Also, even when an interleaver (for example, an LCI) which can begenerated based on a calculation equation is used, the same can occur.

Accordingly, it is desirable to provide a structure that makes itpossible to reduce overlap of values of interleavers between users inthe IDMA system.

(2) Technical Means

In the fifth embodiment, the interleaving unit 153 interleaves a bitsequence of an information block generated from transmission data for auser using an interleaver generated based on a predetermined calculationequation and unique to the user. In particular, the predeterminedcalculation equation includes a shift value according to identificationinformation regarding the user.

Thus, for example, in the IDMA system, it is possible to reduce overlapof the values of the interleavers between the users.

8.2. Technical Features

For example, the interleaving unit 153 acquires an interleaver generatedbased on a predetermined calculation equation and unique to a user. Theinterleaving unit 153 interleaves a bit sequence of an information blockgenerated from transmission data for the user using the interleaver. Inparticular, as described above, the predetermined calculation equationincludes a shift value according to identification information regardinga user. The identification information may be an RNTI.

(1) DI with Shift

As one example, the interleaver is a DI with a shift and is expressed asfollows.

I(m)=((2k+1)m(m+1)/2+S(k))mod N  [Math. 8]

The calculation equation is an equation in which S(k) is added to anormal calculation equation for a DI, as described above. Here, k is auser ID and S(k) is a shift value according to the user ID. Because ofaddition of S(k), I(0) differs according to a user. The user ID may bean RNTI.

(b) LCI with Shift

As another example, the interleaver may be an LCI with a shift or may beexpressed as follows.

I(m)=(aI(m−1)+b+S(k))mod N

I(0)∈{0,N−1}  [Math. 9]

The calculation equation is an equation in which S(k) is added to anormal calculation equation for an LCI, as described above. Here, k is auser ID and S(k) is a shift value according to the user ID. Because ofaddition of S(k), I(1) differs according to a user. The user ID may bean RNTI.

(c) Others

For example, the transmission data is a transport block.

For example, the information block is a codeword. Alternatively, theinformation block may be a code block.

The fifth embodiment has been described above. The technical featuresaccording to the fifth embodiment may also be applied to the first tofourth embodiments.

9. Application Examples

The technology of an embodiment of the present disclosure is applicableto various products. For example, the radio communication apparatus (thefirst radio communication apparatus 100 or the second radiocommunication apparatus 200) may be realized as any type of evolved NodeB (eNB) such as a macro eNB or a small eNB. A small eNB may be an eNBthat covers a cell smaller than a macro cell, such as a pico eNB, microeNB, or home (femto) eNB. Instead, the radio communication apparatus maybe realized as any other types of base stations such as a NodeB and abase transceiver station (BTS). The radio communication apparatus mayinclude a main body (that is also referred to as a base stationapparatus) configured to control radio communication, and one or moreremote radio heads (RRH) disposed in a different place from the mainbody. Additionally, various types of terminals to be discussed later mayalso operate as the radio communication apparatus by temporarily orsemi-permanently executing a base station function. Furthermore, atleast a part of elements of the radio communication apparatus may berealized in the base station apparatus or a module for the base stationapparatus.

For example, the radio communication apparatus (the first radiocommunication apparatus 100 or the second radio communication apparatus200) may be realized as a mobile terminal such as a smartphone, a tabletpersonal computer (PC), a notebook PC, a portable game terminal, aportable/dongle type mobile router, and a digital camera, or anin-vehicle terminal such as a car navigation apparatus. The radiocommunication apparatus may also be realized as a terminal (that is alsoreferred to as a machine type communication (MTC) terminal) thatperforms machine-to-machine (M2M) communication. Furthermore, at least apart of elements of the radio communication apparatus may be realized ina module (such as an integrated circuit module including a single die)mounted on each of the terminals.

First Application Example

FIG. 27 is a block diagram illustrating a first example of a schematicconfiguration of an eNB to which the technology of an embodiment of thepresent disclosure may be applied. An eNB 800 includes one or moreantennas 810 and a base station apparatus 820. Each antenna 810 and thebase station apparatus 820 may be connected to each other via an RFcable.

Each of the antennas 810 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the base station apparatus 820 to transmit and receive radiosignals. The eNB 800 may include the multiple antennas 810, asillustrated in FIG. 27 . For example, the multiple antennas 810 may becompatible with multiple frequency bands used by the eNB 800. AlthoughFIG. 27 illustrates the example in which the eNB 800 includes themultiple antennas 810, the eNB 800 may also include a single antenna810.

The base station apparatus 820 includes a controller 821, a memory 822,a network interface 823, and a radio communication interface 825.

The controller 821 may be, for example, a CPU or a DSP, and operatesvarious functions of a higher layer of the base station apparatus 820.For example, the controller 821 generates a data packet from data insignals processed by the radio communication interface 825, andtransfers the generated packet via the network interface 823. Thecontroller 821 may bundle data from multiple base band processors togenerate the bundled packet, and transfer the generated bundled packet.The controller 821 may have logical functions of performing control suchas radio resource control, radio bearer control, mobility management,admission control, and scheduling. The control may be performed incorporation with an eNB or a core network node in the vicinity. Thememory 822 includes RAM and ROM, and stores a program that is executedby the controller 821, and various types of control data (such as aterminal list, transmission power data, and scheduling data).

The network interface 823 is a communication interface for connectingthe base station apparatus 820 to a core network 824. The controller 821may communicate with a core network node or another eNB via the networkinterface 823. In that case, the eNB 800, and the core network node orthe other eNB may be connected to each other through a logical interface(such as an S1 interface and an X2 interface). The network interface 823may also be a wired communication interface or a radio communicationinterface for radio backhaul. If the network interface 823 is a radiocommunication interface, the network interface 823 may use a higherfrequency band for radio communication than a frequency band used by theradio communication interface 825.

The radio communication interface 825 supports any cellularcommunication scheme such as Long Term Evolution (LTE) and LTE-Advanced,and provides radio connection to a terminal positioned in a cell of theeNB 800 via the antenna 810. The radio communication interface 825 maytypically include, for example, a baseband (BB) processor 826 and an RFcircuit 827. The BB processor 826 may perform, for example,encoding/decoding, modulating/demodulating, andmultiplexing/demultiplexing, and performs various types of signalprocessing of layers (such as L1, medium access control (MAC), radiolink control (RLC), and a packet data convergence protocol (PDCP)). TheBB processor 826 may have a part or all of the above-described logicalfunctions instead of the controller 821. The BB processor 826 may be amemory that stores a communication control program, or a module thatincludes a processor and a related circuit configured to execute theprogram. Updating the program may allow the functions of the BBprocessor 826 to be changed. The module may be a card or a blade that isinserted into a slot of the base station apparatus 820. Alternatively,the module may also be a chip that is mounted on the card or the blade.Meanwhile, the RF circuit 827 may include, for example, a mixer, afilter, and an amplifier, and transmits and receives radio signals viathe antenna 810.

The radio communication interface 825 may include the multiple BBprocessors 826, as illustrated in FIG. 27 . For example, the multiple BBprocessors 826 may be compatible with multiple frequency bands used bythe eNB 800. The radio communication interface 825 may include themultiple RF circuits 827, as illustrated in FIG. 27 . For example, themultiple RF circuits 827 may be compatible with multiple antennaelements. Although FIG. 27 illustrates the example in which the radiocommunication interface 825 includes the multiple BB processors 826 andthe multiple RF circuits 827, the radio communication interface 825 mayalso include a single BB processor 826 or a single RF circuit 827.

In the eNB 800 illustrated in FIG. 27 , the information acquisition unit151 and the interleaving unit 153 described with reference to FIG. 2 maybe mounted on the radio communication interface 825. As one example, amodule that includes a part (for example, the BB processor 826) or allof the radio communication interface 825 may be mounted on the eNB 800,and the information acquisition unit 151 and the interleaving unit 153may be mounted on the module. In this case, the module may store aprogram causing a processor to function as the information acquisitionunit 151 and the interleaving unit 153 (in other words, a programcausing a processor to execute operations of the information acquisitionunit 151 and the interleaving unit 153) and may execute the program. Asanother example, a program causing a processor to function as theinformation acquisition unit 151 and the interleaving unit 153 may beinstalled in the eNB 800 and the radio communication interface 825 (forexample, the BB processor 826) may execute the program. As describedabove, as an apparatus that includes the information acquisition unit151 and the interleaving unit 153, the eNB 800, the base stationapparatus 820, or the module may be provided or a program causing aprocessor to function as the information acquisition unit 151 and theinterleaving unit 153 may be provided. Further, a readable recordingmedium that records the program may be provided. For these points, theinformation acquisition unit 251 and the de-interleaving unit 253described with reference to FIG. 5 are the same as the informationacquisition unit 151 and the interleaving unit 153.

Furthermore, in the eNB 800 illustrated in FIG. 27 , the radiocommunication unit 120 described by using FIG. 2 may be implemented bythe radio communication interface 825 (e.g., the RF circuit 827).Further, the antenna 110 may also be implemented by the antenna 810. Forthis point, the antenna unit 210 and the radio communication unit 220described with reference to FIG. 5 are the same as the antenna unit 110and the radio communication unit 120.

Second Application Example

FIG. 28 is a block diagram illustrating a second example of a schematicconfiguration of an eNB to which the technology of an embodiment of thepresent disclosure may be applied. An eNB 830 includes one or moreantennas 840, a base station apparatus 850, and an RRH 860. Each antenna840 and the RRH 860 may be connected to each other via an RF cable. Thebase station apparatus 850 and the RRH 860 may be connected to eachother via a high speed line such as an optical fiber cable.

Each of the antennas 840 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the RRH 860 to transmit and receive radio signals. The eNB 830may include the multiple antennas 840, as illustrated in FIG. 28 . Forexample, the multiple antennas 840 may be compatible with multiplefrequency bands used by the eNB 830. Although FIG. 28 illustrates theexample in which the eNB 830 includes the multiple antennas 840, the eNB830 may also include a single antenna 840.

The base station apparatus 850 includes a controller 851, a memory 852,a network interface 853, a radio communication interface 855, and aconnection interface 857. The controller 851, the memory 852, and thenetwork interface 853 are the same as the controller 821, the memory822, and the network interface 823 described with reference to FIG. 27 .

The radio communication interface 855 supports any cellularcommunication scheme such as LTE and LTE-Advanced, and provides radiocommunication to a terminal positioned in a sector corresponding to theRRH 860 via the RRH 860 and the antenna 840. The radio communicationinterface 855 may typically include, for example, a BB processor 856.The BB processor 856 is the same as the BB processor 826 described withreference to FIG. 27 , except the BB processor 856 is connected to theRF circuit 864 of the RRH 860 via the connection interface 857. Theradio communication interface 855 may include the multiple BB processors856, as illustrated in FIG. 28 . For example, the multiple BB processors856 may be compatible with multiple frequency bands used by the eNB 830.Although FIG. 28 illustrates the example in which the radiocommunication interface 855 includes the multiple BB processors 856, theradio communication interface 855 may also include a single BB processor856.

The connection interface 857 is an interface for connecting the basestation apparatus 850 (radio communication interface 855) to the RRH860. The connection interface 857 may also be a communication module forcommunication in the above-described high speed line that connects thebase station apparatus 850 (radio communication interface 855) to theRRH 860.

The RRH 860 includes a connection interface 861 and a radiocommunication interface 863.

The connection interface 861 is an interface for connecting the RRH 860(radio communication interface 863) to the base station apparatus 850.The connection interface 861 may also be a communication module forcommunication in the above-described high speed line.

The radio communication interface 863 transmits and receives radiosignals via the antenna 840. The radio communication interface 863 maytypically include, for example, the RF circuit 864. The RF circuit 864may include, for example, a mixer, a filter, and an amplifier, andtransmits and receives radio signals via the antenna 840. The radiocommunication interface 863 may include multiple RF circuits 864, asillustrated in FIG. 28 . For example, the multiple RF circuits 864 maysupport multiple antenna elements. Although FIG. 28 illustrates theexample in which the radio communication interface 863 includes themultiple RF circuits 864, the radio communication interface 863 may alsoinclude a single RF circuit 864.

In the eNB 830 illustrated in FIG. 28 , the information acquisition unit151 and the interleaving unit 153 described with reference to FIG. 2 maybe mounted on the radio communication interface 855 or the radiocommunication interface 863. As one example, a module that includes apart (for example, the BB processor 856) or all of the radiocommunication interface 855 may be mounted on the eNB 830, and theinformation acquisition unit 151 and the interleaving unit 153 may bemounted on the module. In this case, the module may store a programcausing a processor to function as the information acquisition unit 151and the interleaving unit 153 (in other words, a program causing aprocessor to execute operations of the information acquisition unit 151and the interleaving unit 153) and may execute the program. As anotherexample, a program causing a processor to function as the informationacquisition unit 151 and the interleaving unit 153 may be installed inthe eNB 830 and the radio communication interface 855 (for example, theBB processor 856) may execute the program. As described above, as anapparatus that includes the information acquisition unit 151 and theinterleaving unit 153, the eNB 830, the base station apparatus 820, orthe module may be provided or a program causing a processor to functionas the information acquisition unit 151 and the interleaving unit 153may be provided. Further, a readable recording medium that records theprogram may be provided. For these points, the information acquisitionunit 251 and the de-interleaving unit 253 described with reference toFIG. 5 are the same as the information acquisition unit 151 and theinterleaving unit 153.

Furthermore, in the eNB 830 illustrated in FIG. 28 , the radiocommunication unit 120 described by using, for example, FIG. 2 may beimplemented by the radio communication interface 863 (e.g., the RFcircuit 864). Further, the antenna 110 may also be implemented by theantenna 840. For this point, the antenna unit 210 and the radiocommunication unit 220 described with reference to FIG. 5 are the sameas the antenna unit 110 and the radio communication unit 120.

Third Application Example

FIG. 29 is a block diagram illustrating an example of a schematicconfiguration of a smartphone 900 to which the technology of anembodiment of the present disclosure may be applied. The smartphone 900includes a processor 901, a memory 902, a storage 903, an externalconnection interface 904, a camera 906, a sensor 907, a microphone 908,an input device 909, a display device 910, a speaker 911, a radiocommunication interface 912, one or more antenna switches 915, one ormore antennas 916, a bus 917, a battery 918, and an auxiliary controller919.

The processor 901 may be, for example, a CPU or a system on a chip(SoC), and controls functions of an application layer and another layerof the smartphone 900. The memory 902 includes RAM and ROM, and stores aprogram that is executed by the processor 901, and data. The storage 903may include a storage medium such as a semiconductor memory and a harddisk. The external connection interface 904 is an interface forconnecting an external device such as a memory card and a universalserial bus (USB) device to the smartphone 900.

The camera 906 includes an image sensor such as a charge coupled device(CCD) and a complementary metal oxide semiconductor (CMOS), andgenerates a captured image. The sensor 907 may include a group ofsensors such as a measurement sensor, a gyro sensor, a geomagneticsensor, and an acceleration sensor. The microphone 908 converts soundsthat are input to the smartphone 900 to audio signals. The input device909 includes, for example, a touch sensor configured to detect touchonto a screen of the display device 910, a keypad, a keyboard, a button,or a switch, and receives an operation or an information input from auser. The display device 910 includes a screen such as a liquid crystaldisplay (LCD) and an organic light-emitting diode (OLED) display, anddisplays an output image of the smartphone 900. The speaker 911 convertsaudio signals that are output from the smartphone 900 to sounds.

The radio communication interface 912 supports any cellularcommunication scheme such as LTE and LTE-Advanced, and performs radiocommunication. The radio communication interface 912 may typicallyinclude, for example, a BB processor 913 and an RF circuit 914. The BBprocessor 913 may perform, for example, encoding/decoding,modulating/demodulating, and multiplexing/demultiplexing, and performsvarious types of signal processing for radio communication. Meanwhile,the RF circuit 914 may include, for example, a mixer, a filter, and anamplifier, and transmits and receives radio signals via the antenna 916.The radio communication interface 913 may also be a one chip module thathas the BB processor 913 and the RF circuit 914 integrated thereon. Theradio communication interface 912 may include the multiple BB processors913 and the multiple RF circuits 914, as illustrated in FIG. 29 .Although FIG. 29 illustrates the example in which the radiocommunication interface 913 includes the multiple BB processors 913 andthe multiple RF circuits 914, the radio communication interface 912 mayalso include a single BB processor 913 or a single RF circuit 914.

Furthermore, in addition to a cellular communication scheme, the radiocommunication interface 912 may support another type of radiocommunication scheme such as a short-distance wireless communicationscheme, a near field communication scheme, and a radio local areanetwork (LAN) scheme. In that case, the radio communication interface912 may include the BB processor 913 and the RF circuit 914 for eachradio communication scheme.

Each of the antenna switches 915 switches connection destinations of theantennas 916 among multiple circuits (such as circuits for differentradio communication schemes) included in the radio communicationinterface 912.

Each of the antennas 916 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the radio communication interface 912 to transmit and receiveradio signals. The smartphone 900 may include the multiple antennas 916,as illustrated in FIG. 29 . Although FIG. 29 illustrates the example inwhich the smartphone 900 includes the multiple antennas 916, thesmartphone 900 may also include a single antenna 916.

Furthermore, the smartphone 900 may include the antenna 916 for eachradio communication scheme. In that case, the antenna switches 915 maybe omitted from the configuration of the smartphone 900.

The bus 917 connects the processor 901, the memory 902, the storage 903,the external connection interface 904, the camera 906, the sensor 907,the microphone 908, the input device 909, the display device 910, thespeaker 911, the radio communication interface 912, and the auxiliarycontroller 919 to each other. The battery 918 supplies power to blocksof the smartphone 900 illustrated in FIG. 29 via feeder lines, which arepartially shown as dashed lines in the figure. The auxiliary controller919 operates a minimum necessary function of the smartphone 900, forexample, in a sleep mode.

In the smartphone 900 illustrated in FIG. 29 , the informationacquisition unit 151 and the interleaving unit 153 described withreference to FIG. 2 may be mounted on the radio communication interface912. As one example, a module that includes a part (for example, the BBprocessor 913) or all of the radio communication interface 912 may bemounted on the smartphone 900, and the information acquisition unit 151and the interleaving unit 153 may be mounted on the module. In thiscase, the module may store a program causing a processor to function asthe information acquisition unit 151 and the interleaving unit 153 (inother words, a program causing a processor to execute operations of theinformation acquisition unit 151 and the interleaving unit 153) and mayexecute the program. As another example, a program causing a processorto function as the information acquisition unit 151 and the interleavingunit 153 may be installed in the smartphone 900 and the radiocommunication interface 912 (for example, the BB processor 913) mayexecute the program. As described above, as an apparatus that includesthe information acquisition unit 151 and the interleaving unit 153, thesmartphone 900, or the module may be provided or a program causing aprocessor to function as the information acquisition unit 151 and theinterleaving unit 153 may be provided. Further, a readable recordingmedium that records the program may be provided. For these points, theinformation acquisition unit 251 and the de-interleaving unit 253described with reference to FIG. 5 are the same as the informationacquisition unit 151 and the interleaving unit 153.

Furthermore, in the smartphone 900 illustrated in FIG. 29 , the radiocommunication unit 120 described by using FIG. 2 may be implemented bythe radio communication interface 912 (e.g., the RF circuit 914).Further, the antenna 110 may also be implemented by the antenna 916. Forthis point, the antenna unit 210 and the radio communication unit 220described with reference to FIG. 5 are the same as the antenna unit 110and the radio communication unit 120.

Fourth Application Example

FIG. 30 is a block diagram illustrating an example of a schematicconfiguration of a car navigation apparatus 920 to which the technologyof an embodiment of the present disclosure may be applied. The carnavigation apparatus 920 includes a processor 921, a memory 922, aglobal positioning system (GPS) module 924, a sensor 925, a datainterface 926, a content player 927, a storage medium interface 928, aninput device 929, a display device 930, a speaker 931, a radiocommunication interface 933, one or more antenna switches 936, one ormore antennas 937, and a battery 938.

The processor 921 may be, for example, a CPU or a SoC, and controls anavigation function and another function of the car navigation apparatus920. The memory 922 includes RAM and ROM, and stores a program that isexecuted by the processor 921, and data.

The GPS module 924 uses GPS signals received from a GPS satellite tomeasure a position (such as latitude, longitude, and altitude) of thecar navigation apparatus 920. The sensor 925 may include a group ofsensors such as a gyro sensor, a geomagnetic sensor, and a barometricsensor. The data interface 926 is connected to, for example, anin-vehicle network 941 via a terminal that is not shown, and acquiresdata generated by the vehicle, such as vehicle speed data.

The content player 927 reproduces content stored in a storage medium(such as a CD and a DVD) that is inserted into the storage mediuminterface 928. The input device 929 includes, for example, a touchsensor configured to detect touch onto a screen of the display device930, a button, or a switch, and receives an operation or an informationinput from a user. The display device 930 includes a screen such as aLCD or an OLED display, and displays an image of the navigation functionor content that is reproduced. The speaker 931 outputs sounds of thenavigation function or the content that is reproduced.

The radio communication interface 933 supports any cellularcommunication scheme such as LET and LTE-Advanced, and performs radiocommunication. The radio communication interface 933 may typicallyinclude, for example, a BB processor 934 and an RF circuit 935. The BBprocessor 934 may perform, for example, encoding/decoding,modulating/demodulating, and multiplexing/demultiplexing, and performsvarious types of signal processing for radio communication. Meanwhile,the RF circuit 935 may include, for example, a mixer, a filter, and anamplifier, and transmits and receives radio signals via the antenna 937.The radio communication interface 933 may be a one chip module havingthe BB processor 934 and the RF circuit 935 integrated thereon. Theradio communication interface 933 may include the multiple BB processors934 and the multiple RF circuits 935, as illustrated in FIG. 30 .Although FIG. 30 illustrates the example in which the radiocommunication interface 933 includes the multiple BB processors 934 andthe multiple RF circuits 935, the radio communication interface 933 mayalso include a single BB processor 934 or a single RF circuit 935.

Furthermore, in addition to a cellular communication scheme, the radiocommunication interface 933 may support another type of radiocommunication scheme such as a short-distance wireless communicationscheme, a near field communication scheme, and a radio LAN scheme. Inthat case, the radio communication interface 933 may include the BBprocessor 934 and the RF circuit 935 for each radio communicationscheme.

Each of the antenna switches 936 switches connection destinations of theantennas 937 among multiple circuits (such as circuits for differentradio communication schemes) included in the radio communicationinterface 933.

Each of the antennas 937 includes a single or multiple antenna elements(such as multiple antenna elements included in an MIMO antenna), and isused for the radio communication interface 933 to transmit and receiveradio signals. The car navigation apparatus 920 may include the multipleantennas 937, as illustrated in FIG. 30 . Although FIG. 30 illustratesthe example in which the car navigation apparatus 920 includes themultiple antennas 937, the car navigation apparatus 920 may also includea single antenna 937.

Furthermore, the car navigation apparatus 920 may include the antenna937 for each radio communication scheme. In that case, the antennaswitches 936 may be omitted from the configuration of the car navigationapparatus 920.

The battery 938 supplies power to blocks of the car navigation apparatus920 illustrated in FIG. 30 via feeder lines that are partially shown asdashed lines in the figure. The battery 938 accumulates power suppliedfrom the vehicle.

In the car navigation apparatus 920 illustrated in FIG. 30 , theinformation acquisition unit 151 and the interleaving unit 153 describedwith reference to FIG. 2 may be mounted on the radio communicationinterface 933. As one example, a module that includes a part (forexample, the BB processor 934) or all of the radio communicationinterface 933 may be mounted on the car navigation apparatus 920, andthe information acquisition unit 151 and the interleaving unit 153 maybe mounted on the module. In this case, the module may store a programcausing a processor to function as the information acquisition unit 151and the interleaving unit 153 (in other words, a program causing aprocessor to execute operations of the information acquisition unit 151and the interleaving unit 153) and may execute the program. As anotherexample, a program causing a processor to function as the informationacquisition unit 151 and the interleaving unit 153 may be installed inthe car navigation apparatus 920 and the radio communication interface933 (for example, the BB processor 934) may execute the program. Asdescribed above, as an apparatus that includes the informationacquisition unit 151 and the interleaving unit 153, the car navigationapparatus 920, or the module may be provided or a program causing aprocessor to function as the information acquisition unit 151 and theinterleaving unit 153 may be provided. Further, a readable recordingmedium that records the program may be provided. For these points, theinformation acquisition unit 251 and the de-interleaving unit 253described with reference to FIG. 5 are the same as the informationacquisition unit 151 and the interleaving unit 153.

Furthermore, in the car navigation apparatus 920 illustrated in FIG. 30, the radio communication unit 120 described by using FIG. 2 may beimplemented by the radio communication interface 933 (e.g., the RFcircuit 935). Further, the antenna 110 may also be implemented by theantenna 937. For this point, the antenna unit 210 and the radiocommunication unit 220 described with reference to FIG. 5 are the sameas the antenna unit 110 and the radio communication unit 120.

The technology of an embodiment of the present disclosure may also berealized as an in-vehicle system (or a vehicle) 940 including one ormore blocks of the car navigation apparatus 920, the in-vehicle network941, and a vehicle module 942. That is, the in-vehicle system (or avehicle) 940 may be provided as an apparatus including the informationacquisition unit 151 and the interleaving unit 153 (or the informationacquisition unit 251 and the de-interleaving unit 253). The vehiclemodule 942 generates vehicle data such as vehicle speed, engine speed,and trouble information, and outputs the generated data to thein-vehicle network 941.

10. Conclusion

The apparatuses and the processes according to the embodiments of thepresent disclosure have been described above with reference to FIGS. 1to 30 .

(1) First Embodiment

According to the first embodiment, the first radio communicationapparatus 100 includes the information acquisition unit 151 thatacquires an information block generated from transmission data for auser and subjected to error correction coding and the interleaving unit153 that interleaves a bit sequence of the information block using aninterleaver unique to the user. In particular, the interleaving unit 153interleaves the bit sequence by interleaving two or more partialsequences obtained from the bit sequence.

Furthermore, in the first embodiment, each of the two or more partialsequences is included in the bit sequence and does not overlap the otherof the two or more partial sequences.

Thus, for example, it is possible to transmit data more flexibly andwith a lesser burden in the IDMA system. More specifically, for example,in the IDMA system, it is possible to transmit a bit sequence which hasany length without transmitting and receiving interleavers between atransmission side and a reception side.

(2) Second Embodiment

According to the second embodiment, the first radio communicationapparatus 100 includes the information acquisition unit 151 thatacquires an information block generated from transmission data for auser and subjected to error correction coding and the interleaving unit153 that interleaves a bit sequence of the information block using aninterleaver unique to the user. In particular, the interleaving unit 153interleaves the bit sequence by interleaving two or more partialsequences obtained from the bit sequence.

Furthermore, according to the second embodiment, at least one of the twoor more partial sequences includes a part of a sequence obtained byinterleaving the other of the two or more partial sequences. That is, atleast a part of the bit sequence is interleaved repeatedly.

Thus, for example, it is possible to transmit data more flexibly andwith a lesser burden in the IDMA system. More specifically, for example,in the IDMA system, it is possible to transmit a bit sequence which hasany length without transmitting and receiving interleavers between atransmission side and a reception side.

(3) Third Embodiment

According to the third embodiment, the first radio communicationapparatus 100 includes the information acquisition unit 151 thatacquires an information block generated from transmission data for auser and subjected to error correction coding and the interleaving unit153 that interleaves a bit sequence of the information block usinganother interleaver obtained from an interleaver longer than the bitsequence of the information block and unique to the user or aninterleaver unique to the user.

Thus, for example, it is possible to transmit data more flexibly andwith a lesser burden in the IDMA system. More specifically, for example,in the IDMA system, it is possible to transmit a bit sequence which hasany length without transmitting and receiving interleavers between atransmission side and a reception side.

(4) Fourth Embodiment

According to the fourth embodiment, the first radio communicationapparatus 100 includes the information acquisition unit 151 thatacquires an information block generated from transmission data for auser and the interleaving unit 153 that interleaves a bit sequence ofthe information block using an interleaver unique to the user. Inparticular, the information block is a block after segmentation forerror correction coding and the error correction coding and beforeintegration after the error correction coding.

Thus, for example, it is possible to further narrow the range of thelength of the bit sequence which is the interleaving target in the IDMAsystem.

(5) Fifth Embodiment

According to the fifth embodiment, the first radio communicationapparatus 100 includes the interleaving unit 153 that interleaves a bitsequence of an information block generated from transmission data for auser using an interleaver generated based on a predetermined calculationequation and unique to the user. In particular, the predeterminedcalculation equation includes a shift value according to identificationinformation regarding the user.

Accordingly, for example, it is desirable to provide a structure thatmakes it possible to reduce overlap of values of interleavers betweenusers in the IDMA system.

The preferred embodiment of the present disclosure has been describedabove with reference to the accompanying drawings, whilst the presentdisclosure is not limited to the above examples. A person skilled in theart may find various alterations and modifications within the scope ofthe appended claims, and it should be understood that they willnaturally come under the technical scope of the present disclosure.

For example, the example in which an interleaver unique to a user isused to interleave a bit sequence of an information block (for example,a codeword or a code block) generated from transmission data (forexample, a transport block) for the user has been described. In thepresent disclosure, the interleaver may be an interleaver which isunique to the user and unique to the transmission data (for example, atransport block) or the information block (for example, a codeword or acode block). For example, the interleaver unique to the transmissiondata or the information block may be generated by applying a shiftunique to the transmission data or the information block to theinterleaver unique to the user.

Further, it is not always necessary to execute the processing steps inthe processing in the present specification in chronological order inorder described in the flowcharts or the sequence diagrams. For example,the processing steps in the above-described processing may be executedin order different from the order described in the flowcharts or thesequence diagrams or may be executed in parallel.

Further, a computer program (in other words, a computer program causingthe processor to perform operations of constituent elements of theapparatus) that causes a processor (for example, a CPU or a DSP)including an apparatus (for example, a radio communication apparatus ora module for the radio communication apparatus) according to the presentspecification to function as the constituent elements (for example, aninformation acquisition unit, and an interleaving unit or ade-interleaving unit) of the apparatus can be generated. A recordingmedium that records the computer program may also be provided. Anapparatus (for example, a radio communication apparatus or a module forthe radio communication apparatus) including a memory that stores thecomputer program and one or more processors that is capable of executingthe computer program may be provided. A method including operations ofconstituent elements (for example, an information acquisition unit, andan interleaving unit or a de-interleaving unit) of the apparatus is alsoincluded in a technology according to the present disclosure.

Further, the effects described in this specification are merelyillustrative or exemplified effects, and are not limitative. That is,with or in the place of the above effects, the technology according tothe present disclosure may achieve other effects that are clear to thoseskilled in the art from the description of this specification.

Additionally, the present technology may also be configured as below.

(1)

An apparatus including:

-   -   an acquisition unit configured to acquire an information block        generated from transmission data for a user and subjected to        error correction coding; and    -   an interleaving unit configured to interleave a bit sequence of        the information block using an interleaver unique to the user,    -   wherein the interleaving unit interleaves the bit sequence by        interleaving each of two or more partial sequences obtained from        the bit sequence.

(2)

The apparatus according to (1),

-   -   wherein each of the two or more partial sequence has a length of        a power of two.

(3)

The apparatus according to (1) or (2),

-   -   wherein the bit sequence has a length which is not a power of        two.

(4)

The apparatus according to any one of (1) to (3),

-   -   wherein the information block is a codeword or a code block.

(5)

The apparatus according to any one of (1) to (4),

-   -   wherein the interleaving unit interleaves each of the two or        more partial sequences using a corresponding interleaver, and    -   the corresponding interleaver is an interleaver which has a same        length as a length of the partial sequence and is unique to the        user.

(6)

The apparatus according to any one of (1) to (5),

-   -   wherein each of the two or more partial sequences is included in        the bit sequence and does not overlap the other of the two or        more partial sequences.

(7)

The apparatus according to (6),

-   -   wherein a total sum of lengths of the two or more partial        sequences is equal to a length of the bit sequence.

(8)

The apparatus according to (6) or (7),

-   -   wherein the two or more partial sequences have different        lengths.

(9)

The apparatus according to any one of (6) to (8),

-   -   wherein the interleaving unit interleaves the two or more        partial sequences in parallel.

(10)

The apparatus according to any one of (6) to (9),

-   -   wherein the interleaving unit interleaves the bit sequence using        one concatenated interleaver which includes an interleaver        corresponding to each of the two or more partial sequences and        has a same length as a length of the bit sequence, and    -   the interleaver corresponding to each of the two or more partial        sequences is an interleaver which has a same length as a length        of the partial sequence and is unique to the user.

(11)

The apparatus according to any one of (1) to (5),

-   -   wherein at least one of the two or more partial sequences        includes a part of a sequence obtained by interleaving the other        of the two or more partial sequences.

(12)

The apparatus according to (11),

-   -   wherein the at least one of the partial sequences further        includes a part of the bit sequence.

(13)

The apparatus according to (11) or (12),

-   -   wherein a total sum of lengths of the two or more partial        sequences is greater than a length of the bit sequence.

(14)

The apparatus according to any one of (11) to (13),

-   -   wherein the two or more partial sequences have a same length.

(15)

The apparatus according to any one of (11) to (14),

-   -   wherein a length of each of the two or more partial sequences is        a length according to a length of the bit sequence among a        plurality of predetermined lengths.

(16)

The apparatus according to (15),

-   -   wherein a length of at least one of the two or more partial        sequences is a maximum length among one or more lengths equal to        or less than the length of the bit sequence and included in the        plurality of predetermined lengths.

(17)

The apparatus according to any one of (11) to (16),

-   -   wherein a length of each of the two or more partial sequences is        one predetermined length.

(18)

An apparatus including:

-   -   an acquisition unit configured to acquire a received bit        sequence; and    -   a de-interleaving unit configured to generate a bit sequence of        an information block not subjected to error correction decoding        by de-interleaving the received bit sequence using a        de-interleaver corresponding to an interleaver unique to a user,    -   wherein the de-interleaving unit de-interleaves the received bit        sequence by de-interleaving each of two or more partial        sequences obtained from the received bit sequence.

(19)

An apparatus including:

-   -   an acquisition unit configured to acquire an information block        generated from transmission data for a user and subjected to        error correction coding; and    -   an interleaving unit configured to interleave a bit sequence        using an interleaver unique to the user or another interleaver        obtained from the interleaver unique to the user and longer than        the bit sequence of the information block.

(20)

The apparatus according to (19),

-   -   wherein the interleaver unique to the user is an interleaver        which has a length of a power of two.

(21)

The apparatus according to (19) or (20),

-   -   wherein the other interleaver is an interleaver which has the        same length as a length of the bit sequence of the information        block.

(22)

The apparatus according to (21),

-   -   wherein the other interleaver is an interleaver obtained by        excluding a portion in which input bits are output to bits not        included in an output bit sequence which has a same length as        the length of the bit sequence from the interleaver unique to        the user.

(23)

The apparatus according to any one of (19) to (22),

-   -   wherein the bit sequence has a length which is not a power of        two.

(24)

The apparatus according to any one of (19) to (23),

-   -   wherein the information block is a codeword or a code block.

(25)

An apparatus including:

-   -   an acquisition unit configured to acquire a received bit        sequence; and    -   a de-interleaving unit configured to generate a bit sequence of        an information block not subjected to error correction decoding        by de-interleaving the received bit sequence using a        de-interleaver corresponding to another interleaver obtained        from an interleaver longer than the received bit sequence and        unique to a user.

(26)

An apparatus including:

-   -   an acquisition unit configured to acquire an information block        generated from transmission data for a user; and    -   an interleaving unit configured to interleave a bit sequence of        the information block using an interleaver unique to the user,    -   wherein the information block is a block after segmentation for        error correction coding and the error correction coding and        before integration after the error correction coding.

(27)

The apparatus according to (26),

-   -   wherein the information block is a code block.

(28)

The apparatus according to (26) or (27),

-   -   wherein the interleaving unit interleaves a bit sequence of two        or more information blocks corresponding to the same unit block        using the same interleaver.

(29)

The apparatus according to any one of (26) to (28),

-   -   wherein the interleaver unique to the user is an interleaver        which has a length of a power of two.

(30)

The apparatus according to any one of (26) to (29),

-   -   wherein the interleaver unique to the user is an interleaver        which is unique to a cell, a unit block larger than the        information block, or a link direction.

(31)

The apparatus according to any one of (26) to (30),

-   -   wherein the integration after the error correction coding is        concatenation or bit collection of exclusive OR.

(32)

An apparatus including:

-   -   an acquisition unit configured to acquire a received bit        sequence; and    -   a de-interleaving unit configured to generate a bit sequence of        an information block by de-interleaving the received bit        sequence using a de-interleaver corresponding to an interleaver        unique to a user,    -   wherein the information block is a block after segmentation for        error correction decoding and before the error correction        decoding.

(33)

A method comprising: by a processor,

-   -   acquiring information block generated from transmission data for        a user and subjected to error correction coding; and    -   interleaving a bit sequence of the information block using an        interleaver unique to the user,    -   wherein the interleaving of the bit sequence includes        interleaving two or more partial sequences obtained from the bit        sequence.

(34)

A program causing a processor to execute:

-   -   acquiring information block generated from transmission data for        a user and subjected to error correction coding; and    -   interleaving a bit sequence of the information block using an        interleaver unique to the user,    -   wherein the interleaving of the bit sequence includes        interleaving two or more partial sequences obtained from the bit        sequence.

(35)

A readable recording medium having a program recorded thereon, theprogram causing a processor to execute:

-   -   acquiring information block generated from transmission data for        a user and subjected to error correction coding; and    -   interleaving a bit sequence of the information block using an        interleaver unique to the user,    -   wherein the interleaving of the bit sequence includes        interleaving two or more partial sequences obtained from the bit        sequence.

(36)

A method comprising: by a processor,

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block not subjected        to error correction decoding by de-interleaving the received bit        sequence using a de-interleaver corresponding to an interleaver        unique to a user,    -   wherein the de-interleaving of the received bit sequence        includes de-interleaving two or more partial sequences obtained        from the received bit sequence.

(37)

A program causing a processor to execute:

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block not subjected        to error correction decoding by de-interleaving the received bit        sequence using a de-interleaver corresponding to an interleaver        unique to a user,    -   wherein the de-interleaving of the received bit sequence        includes de-interleaving two or more partial sequences obtained        from the received bit sequence.

(38)

A readable recording medium having a program recorded thereon, theprogram causing a processor to execute:

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block not subjected        to error correction decoding by de-interleaving the received bit        sequence using a de-interleaver corresponding to an interleaver        unique to a user,    -   wherein the de-interleaving of the received bit sequence        includes de-interleaving two or more partial sequences obtained        from the received bit sequence.

(39)

A method including: by a processor,

-   -   acquiring an information block generated from transmission data        for a user and subjected to error correction coding; and    -   interleaving a bit sequence using an interleaver unique to the        user or another interleaver obtained from the interleaver unique        to the user and longer than the bit sequence of the information        block.

(40)

A program causing a processor to execute:

-   -   acquiring an information block generated from transmission data        for a user and subjected to error correction coding; and    -   interleaving a bit sequence using an interleaver unique to the        user or another interleaver obtained from the interleaver unique        to the user and longer than the bit sequence of the information        block.

(41)

A readable recording medium having a program recorded thereon, theprogram causing a processor to execute:

-   -   acquiring an information block generated from transmission data        for a user and subjected to error correction coding; and    -   interleaving a bit sequence using an interleaver unique to the        user or another interleaver obtained from the interleaver unique        to the user and longer than the bit sequence of the information        block.

(42)

A method including: by a processor,

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block not subjected        to error correction decoding by de-interleaving the received bit        sequence using a de-interleaver corresponding to another        interleaver obtained from an interleaver longer than the        received bit sequence and unique to a user.

(43)

A program causing a processor to execute:

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block not subjected        to error correction decoding by de-interleaving the received bit        sequence using a de-interleaver corresponding to another        interleaver obtained from an interleaver longer than the        received bit sequence and unique to a user.

(44)

A readable recording medium having a program recorded thereon, theprogram causing a processor to execute:

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block not subjected        to error correction decoding by de-interleaving the received bit        sequence using a de-interleaver corresponding to another        interleaver obtained from an interleaver longer than the        received bit sequence and unique to a user.

(45)

A method including: by a processor,

-   -   acquiring an information block generated from transmission data        for a user; and    -   interleaving a bit sequence of the information block using an        interleaver unique to the user,    -   wherein the information block is a block after segmentation for        error correction coding and the error correction coding and        before integration after the error correction coding.

(46)

A program causing a processor to execute:

-   -   acquiring an information block generated from transmission data        for a user; and interleaving a bit sequence of the information        block using an interleaver unique to the user,    -   wherein the information block is a block after segmentation for        error correction coding and the error correction coding and        before integration after the error correction coding.

(47)

A readable recording medium having a program recorded thereon, theprogram causing a processor to execute:

-   -   acquiring an information block generated from transmission data        for a user; and interleaving a bit sequence of the information        block using an interleaver unique to the user,    -   wherein the information block is a block after segmentation for        error correction coding and the error correction coding and        before integration after the error correction coding.

(48)

An apparatus including: by a processor,

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block by        de-interleaving the received bit sequence using a de-interleaver        corresponding to an interleaver unique to a user,    -   wherein the information block is a block after segmentation for        error correction decoding and before the error correction        decoding.

(49)

A program causing a processor to execute:

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block by        de-interleaving the received bit sequence using a de-interleaver        corresponding to an interleaver unique to a user,    -   wherein the information block is a block after segmentation for        error correction decoding and before the error correction        decoding.

(50)

A readable recording medium having a program recorded thereon, theprogram causing a processor to execute:

-   -   acquiring a received bit sequence; and    -   generating a bit sequence of an information block by        de-interleaving the received bit sequence using a de-interleaver        corresponding to an interleaver unique to a user,    -   wherein the information block is a block after segmentation for        error correction decoding and before the error correction        decoding.

REFERENCE SIGNS LIST

-   -   1 system    -   11, 31, 51, 71 bit sequence    -   13, 33, 43, 53, 65 partial sequence    -   100 first radio communication apparatus    -   150 transmission processing unit    -   151 information acquisition unit    -   153 interleaving unit    -   200 second radio communication apparatus    -   250 reception processing unit    -   251 information acquisition unit    -   253 de-interleaving unit

What is claimed is:
 1. An apparatus, comprising: circuitry configured to: acquire an information block from transmission data, wherein the information block is subjected to an error correction coding operation; and interleave a bit sequence of the information block, wherein the interleave of the bit sequence is based on interleave of each of a plurality of partial sequences obtained from the bit sequence, and a length of each of the plurality of partial sequences is a power of two and is variable.
 2. The apparatus according to claim 1, wherein the circuitry is further configured to interleave each of the plurality of partial sequences by a corresponding interleaver, and a length of the corresponding interleaver is equal to a length of one of the plurality of partial sequences.
 3. The apparatus according to claim 1, wherein: each of the plurality of partial sequences is included in the bit sequence, and a first partial sequence of the plurality of partial sequences non-overlaps with a second partial sequence of the plurality of partial sequences.
 4. The apparatus according to claim 3, wherein a total sum of lengths of the plurality of partial sequences is equal to a length of the bit sequence.
 5. The apparatus according to claim 3, wherein the plurality of partial sequences have different lengths.
 6. The apparatus according to claim 3, wherein the circuitry is further configured to interleave the plurality of partial sequences in parallel.
 7. The apparatus according to claim 3, wherein: the circuitry is further configured to interleave the bit sequence based on a concatenated interleaver, wherein the concatenated interleaver includes a first interleaver corresponding to each of the plurality of partial sequences, and a length of the concatenated interleaver is equal to the length of the bit sequence, a length of the first interleaver corresponding to each of the plurality of partial sequences is equal to a length of one of the plurality of partial sequences, and the concatenated interleaver is unique to a user.
 8. The apparatus according to claim 1, wherein a partial sequence of the plurality of partial sequences further includes a part of the bit sequence.
 9. The apparatus according to claim 1, wherein a total sum of lengths of the partial sequences is greater than a length of the bit sequence.
 10. The apparatus according to claim 1, wherein the plurality of partial sequences have a same length.
 11. The apparatus according to claim 1, wherein the length of each of the plurality of partial sequences is based on a length of the bit sequence, and the length of each of the plurality of partial sequences is among a plurality of lengths.
 12. The apparatus according to claim 1, wherein a length of each of the plurality of partial sequences is a same length.
 13. The apparatus according to claim 1, wherein a first partial sequence of the plurality of partial sequences includes a part of a sequence obtained by interleave of a second partial sequence of the plurality of partial sequences.
 14. An apparatus, comprising: circuitry configured to: acquire a bit sequence; and generate an information block by de-interleave of the acquired bit sequence based on a de-interleaver, wherein the de-interleaver corresponds to an interleaver unique to a user, the de-interleave of the acquired bit sequence is by de-interleave of each of a plurality of partial sequences obtained from the acquired bit sequence, the information block is non-decoded for error correction, and a length of each of the plurality of partial sequences is a power of two.
 15. A method, comprising: acquiring an information block from transmission data; and interleaving a bit sequence of the information block based on interleave of each of a plurality of partial sequences obtained from the bit sequence, wherein the information block is subjected to an error correction coding operation, wherein a length of each of the plurality of partial sequences is a power of two and is variable.
 16. A method, comprising: acquiring a bit sequence; and generating an information block by de-interleave of the acquired bit sequence based on a de-interleaver, wherein the de-interleaver corresponds to an interleaver unique to a user, the de-interleave of the acquired bit sequence is by de-interleave of each of the plurality of partial sequences obtained from the acquired bit sequence, the information block is non-decoded for error correction, and a length of each of the plurality of partial sequences is a power of two. 